GTHX G1 Therapeutics Inc

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14D-9

(Rule 14d-101)

SOLICITATION/RECOMMENDATION STATEMENT

UNDER SECTION 14(d)(4) OF THE SECURITIES EXCHANGE ACT OF 1934

G1 THERAPEUTICS, INC.

(Name of Subject Company)

G1 THERAPEUTICS, INC.

(Name of Persons Filing Statement)

COMMON STOCK PAR VALUE $0.0001 PER SHARE

(Title of Class of Securities)

3621LQ109

(CUSIP Number of Class of Securities)

Monica Roberts Thomas, Esq.

Chief Legal and People Officer

700 Park Offices Drive, Suite 200

Research Triangle Park, NC 27709

With copies to:

(Name, address, and telephone numbers of person authorized to receive notices and communications on behalf of the persons filing statement)

This Schedule 14D-9 filing relates solely to preliminary communications made before the commencement of a planned cash tender offer (the “Offer”) by Genesis Merger Sub, Inc., a Delaware corporation (“Purchaser”) and a wholly owned subsidiary of Pharmacosmos A/S, a Danish Aktieselkab (“Parent”), to acquire all of the issued and outstanding shares of common stock, par value $0.0001 per share, of G1 Therapeutics, Inc., a Delaware corporation (the “Company” or “G1”), to be commenced pursuant to the Agreement and Plan of Merger, dated as of August 6, 2024, by and among Parent, Purchaser and the Company (the “Merger Agreement”). Upon the consummation of the Offer, Purchaser will merge with and into the Company (the “Merger”) pursuant to Section 251(h) of the Delaware General Corporation Law, with the Company as the surviving corporation. This Schedule 14D-9 filing consists of the following documents relating to the proposed Offer and Merger:

Cautionary Note Regarding Forward-Looking Statements

This document contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding the proposed acquisition of G1 by Parent, the expected timetable for completing the transaction, and G1’s future financial or operating performance. The words “may,” “will,” “could,” “would,” “should,” “expect,” “plan,” “anticipate,” “intend,” “believe,” “estimate,” “predict,” “project,” “potential,” “continue,” “seek,” “target” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Any forward-looking statements in this document are based on management’s current expectations and beliefs and are subject to a number of risks, uncertainties and important factors that may cause actual events or results to differ materially from those expressed or implied by any forward-looking statements contained in this document, including, without limitation: (i) risks associated with the timing of the closing of the proposed transaction, including the risks that a condition to closing would not be satisfied within the expected timeframe or at all or that the closing of the proposed transaction will not occur; (ii) uncertainties as to how many of G1’s stockholders will tender their shares in the offer; (iii) the possibility that a governmental entity may prohibit, delay or refuse to grant approval for the consummation of the transaction; (iv) the possibility that competing offers will be made; (v) the outcome of any legal proceedings that may be instituted against the parties and others related to the merger agreement; (vi) unanticipated difficulties or expenditures relating to the proposed transaction, the response of business partners and competitors to the announcement of the proposed transaction, and/or potential difficulties in employee retention as a result of the announcement and pendency of the proposed transaction; (vii) G1’s ability to successfully demonstrate the efficacy and safety of its drug or drug candidates, and the preclinical or clinical results for its product candidates, which may not support further development of such product candidates; (viii) comments, feedback and actions of regulatory agencies; (ix) G1’s dependence on the commercial success of COSELA (trilaciclib); (x) the inherent uncertainties associated with developing new products or technologies and operating as commercial stage company; (xi) chemotherapy shortages; and (xii) other risks identified in G1’s SEC filings, including G1’s Annual Report on Form 10-K for the year ended December 31, 2023, and subsequent filings with the SEC. G1 cautions you not to place undue reliance on any forward-looking statements, which speak only as of the date they are made. G1 disclaims any obligation to publicly update or revise any such statements to reflect any change in expectations or in events, conditions or circumstances on which any such statements may be based, or that may affect the likelihood that actual results will differ from those set forth in the forward-looking statements.

Additional Information and Where to Find It

The tender offer referred to in this document has not yet commenced. This document is for informational purposes only and is neither an offer to purchase nor a solicitation of an offer to sell shares, nor is it a substitute for the tender offer materials that Parent or Purchaser will file with the SEC upon commencement of the tender offer. At the time the tender offer is commenced, Parent and its acquisition subsidiary will cause to be filed a tender offer statement on Schedule TO with the SEC, and G1 will file a solicitation/recommendation statement on Schedule 14D-9 with respect to the tender offer. THE TENDER OFFER STATEMENT (INCLUDING AN OFFER TO PURCHASE, A RELATED LETTER OF TRANSMITTAL AND OTHER OFFER DOCUMENTS) AND THE SOLICITATION/RECOMMENDATION STATEMENT WILL CONTAIN IMPORTANT INFORMATION THAT SHOULD BE READ CAREFULLY AND CONSIDERED BY G1’S STOCKHOLDERS BEFORE ANY DECISION IS MADE WITH RESPECT TO THE TENDER OFFER. Both the tender offer statement and the solicitation/recommendation statement will be mailed to G1’s stockholders free of charge. A free copy of the tender offer statement and the solicitation/recommendation statement will also be made available to all stockholders of G1 by accessing https://investors.g1therapeutics.com or by contacting Investor Relations at ir@g1therapeutics.com. In addition, the tender offer statement and the solicitation/recommendation statement (and all other documents filed with the SEC) will be available at no charge on the SEC’s website: www.sec.gov, upon filing with the SEC.

G1’S STOCKHOLDERS ARE ADVISED TO READ THE SCHEDULE TO AND THE SCHEDULE 14D-9, AS EACH MAY BE AMENDED OR SUPPLEMENTED FROM TIME TO TIME, AND ANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC WHEN THEY BECOME AVAILABLE BEFORE THEY MAKE ANY DECISION WITH RESPECT TO THE TENDER OFFER, BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT THE PROPOSED TRANSACTION AND THE PARTIES THERETO.

Exhibit 99.1

August 7, 2024

G1 Colleagues –  

Moments ago, we announced an agreement whereby Pharmacosmos will be acquiring G1 Therapeutics approximately $405 million, or U.S. $7.15 per share, in cash. The full press release we issued is attached. I wanted to provide each of you with background on the rationale for this agreement and give you a sense of who Pharmacosmos is. I’m sure you have more questions than this communication can cover, so we will supplement this with a company town hall today at 10am.

We know that given COSELA is the only product in the market to demonstrate multilineage myeloprotection it is our best hope to fulfill our company mission of “improving the lives of those impacted by cancer.” Like many of you, I was attracted to G1 because I witnessed a loved one diagnosed with cancer and suffer through the numerous myelotoxic challenges of chemotherapy. But through the efforts of every single G1 colleague, we have already started to transform the clinical paradigm and help thousands of ES-SCLC patients better navigate their cancer diagnosis because of the availability of COSELA.

And while we continue to focus on getting more health care providers to adopt Cosela as the new ES-SCLC treatment paradigm, today’s announcement provides the opportunity to move that clinical paradigm change ahead even faster to benefit more patients.

As a global company with extensive experience in supportive care, Pharmacosmos will enable even more rapid availability, access, and adoption for COSELA globally. I have personally seen the clear commitment and experience in supportive care that they have, along with a deep appreciation for what COSELA can represent to patients. The combined entity will clearly offer greater hope to more patients sooner than we could on our own.

I realize that you have many questions during this time of change. We will hold a town hall today at 10am where I will share a bit more about this announcement and where I encourage you to ask questions. I have also attached an employee FAQ to this email. Please be sensitive to any communication around this transaction and as always follow our social media policies. While we may not be able to answer every question at this early stage, we will continue to communicate as transparently as we can going forward.

This announcement is likely to generate increased interest in our company and it is important that we speak with one voice. If you receive inbounds inquiries from media, analysts, shareholders or others, please refer them to Will Roberts (wroberts@g1therapeutics.com).

If there is one take-away message I want you all to remember, it’s that there is still work to be done before we close this transaction. I would ask that we all stay as focused as possible on continuing to execute on our respective responsibilities. There are ES-SCLC patients counting on us to do that.

In conclusion, from a concept in Dr. Ned Sharpless’s head on a flight to California so many years ago, to an approved product, the challenge patients have with cancer has been made more manageable because of the efforts of each of you. I thank you for your continued focus and commitment and know that today’s announcement is an exciting next step on that COSELA journey.

Best Regards,

Jack

Cautionary Note Regarding Forward-Looking Statements

This communication contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding the proposed acquisition of G1 by Pharmacosmos, the expected timetable for completing the transaction, and G1’s future financial or operating performance. The words “may,” “will,” “could,” “would,” “should,” “expect,” “plan,” “anticipate,” “intend,” “believe,” “estimate,” “predict,” “project,” “potential,” “continue,” “seek,” “target” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Any forward-looking statements in this communication are based on management’s current expectations and beliefs and are subject to a number of risks, uncertainties and important factors that may cause actual events or results to differ materially from those expressed or implied by any forward-looking statements contained in this press release, including, without limitation: (i) risks associated with the timing of the closing of the proposed transaction, including the risks that a condition to closing would not be satisfied within the expected timeframe or at all or that the closing of the proposed transaction will not occur; (ii) uncertainties as to how many of G1’s stockholders will tender their shares in the offer; (iii) the possibility that a governmental entity may prohibit, delay or refuse to grant approval for the consummation of the transaction; (iv) the possibility that competing offers will be made; (v) the outcome of any legal proceedings that may be instituted against the parties and others related to the merger agreement; (vi) unanticipated difficulties or expenditures relating to the proposed transaction, the response of business partners and competitors to the announcement of the proposed transaction, and/or potential difficulties in employee retention as a result of the announcement and pendency of the proposed transaction; (vii) G1’s ability to successfully demonstrate the efficacy and safety of its drug or drug candidates, and the preclinical or clinical results for its product candidates, which may not support further development of such product candidates; (viii) comments, feedback and actions of regulatory agencies; (ix) G1’s dependence on the commercial success of COSELA (trilaciclib); (x) the inherent uncertainties associated with developing new products or technologies and operating as commercial stage company; (xi) chemotherapy shortages; and (xii) other risks identified in G1’s SEC filings, including G1’s Annual Report on Form 10-K for the year ended December 31, 2023, and subsequent filings with the SEC. G1 cautions you not to place undue reliance on any forward-looking statements, which speak only as of the date they are made. G1 disclaims any obligation to publicly update or revise any such statements to reflect any change in expectations or in events, conditions or circumstances on which any such statements may be based, or that may affect the likelihood that actual results will differ from those set forth in the forward-looking statements.

Additional Information and Where to Find It

The tender offer referred to in this communication has not yet commenced. This communication is for informational purposes only and is neither an offer to purchase nor a solicitation of an offer to sell shares, nor is it a substitute for the tender offer materials that Pharmacosmos and its acquisition subsidiary will file with the SEC upon commencement of the tender offer. At the time the tender offer is commenced, Pharmacosmos and its acquisition subsidiary will cause to be filed a tender offer statement on Schedule TO with the SEC, and G1 will file a solicitation/recommendation statement on Schedule 14D-9 with respect to the tender offer. THE TENDER OFFER STATEMENT (INCLUDING AN OFFER TO PURCHASE, A RELATED LETTER OF TRANSMITTAL AND OTHER OFFER DOCUMENTS) AND THE SOLICITATION/RECOMMENDATION STATEMENT WILL CONTAIN IMPORTANT INFORMATION THAT SHOULD BE READ CAREFULLY AND CONSIDERED BY G1’S STOCKHOLDERS BEFORE ANY DECISION IS MADE WITH RESPECT TO THE TENDER OFFER. Both the tender offer statement and the solicitation/recommendation statement will be mailed to G1’s stockholders free of charge. A free copy of the tender offer statement and the solicitation/recommendation statement will also be made available to all stockholders of G1 by accessing https://investor.g1therapeutics.com or by contacting Investor Relations at ir@g1therapeutics.com. In addition, the tender offer statement and the solicitation/recommendation statement (and all other documents filed with the SEC) will be available at no charge on the SEC’s website: www.sec.gov, upon filing with the SEC.

G1’S STOCKHOLDERS ARE ADVISED TO READ THE SCHEDULE TO AND THE SCHEDULE 14D-9, AS EACH MAY

BE AMENDED OR SUPPLEMENTED FROM TIME TO TIME, AND ANY OTHER RELEVANT DOCUMENTS FILED WITH

THE SEC WHEN THEY BECOME AVAILABLE BEFORE THEY MAKE ANY DECISION WITH RESPECT TO THE

TENDER OFFER, BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT THE PROPOSED

TRANSACTION AND THE PARTIES THERETO.

Exhibit 99.2

Employee FAQ

Questions about the transaction

Questions about Pharmacosmos

Questions about the impact of the transaction on the G1 team and daily operations

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Questions about GTHX stock, my equity awards and, and compensation and benefits

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How do I answer questions or discuss this transaction?

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Cautionary Note Regarding Forward-Looking Statements

This communication contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding the proposed acquisition of G1 by Pharmacosmos, the expected timetable for completing the transaction, and G1’s future financial or operating performance. The words “may,” “will,” “could,” “would,” “should,” “expect,” “plan,” “anticipate,” “intend,” “believe,” “estimate,” “predict,” “project,” “potential,” “continue,” “seek,” “target” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Any forward-looking statements in this communication are based on management’s current expectations and beliefs and are subject to a number of risks, uncertainties and important factors that may cause actual events or results to differ materially from those expressed or implied by any forward-looking statements contained in this press release, including, without limitation: (i) risks associated with the timing of the closing of the proposed transaction, including the risks that a condition to closing would not be satisfied within the expected timeframe or at all or that the closing of the proposed transaction will not occur; (ii) uncertainties as to how many of G1’s stockholders will tender their shares in the offer; (iii) the possibility that a governmental entity may prohibit, delay or refuse to grant approval for the consummation of the transaction; (iv) the possibility that competing offers will be made; (v) the outcome of any legal proceedings that may be instituted against the parties and others related to the merger agreement; (vi) unanticipated difficulties or expenditures relating to the proposed transaction, the response of business partners and competitors to the announcement of the proposed transaction, and/or potential difficulties in employee retention as a result of the announcement and pendency of the proposed transaction; (vii) G1’s ability to successfully demonstrate the efficacy and safety of its drug or drug candidates, and the preclinical or clinical results for its product candidates, which may not support further development of such product candidates; (viii) comments, feedback and actions of regulatory agencies; (ix) G1’s dependence on the commercial success of COSELA (trilaciclib); (x) the inherent uncertainties associated with developing new products or technologies and operating as commercial stage company; (xi) chemotherapy shortages; and (xii) other risks identified in G1’s SEC filings, including G1’s Annual Report on Form 10-K for the year ended December 31, 2023, and subsequent filings with the SEC. G1 cautions you not to place undue reliance on any forward-looking statements, which speak only as of the date they are made. G1 disclaims any obligation to publicly update or revise any such statements to reflect any change in expectations or in events, conditions or circumstances on which any such statements may be based, or that may affect the likelihood that actual results will differ from those set forth in the forward-looking statements.

Additional Information and Where to Find It

The tender offer referred to in this communication has not yet commenced. This communication is for informational purposes only and is neither an offer to purchase nor a solicitation of an offer to sell shares, nor is it a substitute for the tender offer materials that Pharmacosmos and its acquisition subsidiary will file with the SEC upon commencement of the tender offer. At the time the tender offer is commenced, Pharmacosmos and its acquisition subsidiary will cause to be filed a tender offer statement on Schedule TO with the SEC, and G1 will file a solicitation/recommendation statement on Schedule 14D-9 with respect to the tender offer. THE TENDER OFFER STATEMENT (INCLUDING AN OFFER TO PURCHASE, A RELATED LETTER OF TRANSMITTAL AND OTHER OFFER DOCUMENTS) AND THE SOLICITATION/RECOMMENDATION STATEMENT WILL CONTAIN IMPORTANT INFORMATION THAT SHOULD BE READ CAREFULLY AND CONSIDERED BY G1’S STOCKHOLDERS BEFORE ANY DECISION IS MADE WITH RESPECT TO THE TENDER OFFER. Both the tender offer statement and the solicitation/recommendation statement will be mailed to G1’s stockholders free of charge. A free copy of the tender offer statement and the solicitation/recommendation statement will also be made available to all stockholders of G1 by accessing https://investor.g1therapeutics.com or by contacting Investor Relations at ir@g1therapeutics.com. In addition, the tender offer statement and the solicitation/recommendation statement (and all other documents filed with the SEC) will be available at no charge on the SEC’s website: www.sec.gov, upon filing with the SEC.

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G1’S STOCKHOLDERS ARE ADVISED TO READ THE SCHEDULE TO AND THE SCHEDULE 14D-9, AS EACH MAY BE AMENDED OR SUPPLEMENTED FROM TIME TO TIME, AND ANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC WHEN THEY BECOME AVAILABLE BEFORE THEY MAKE ANY DECISION WITH RESPECT TO THE TENDER OFFER, BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT THE PROPOSED TRANSACTION AND THE PARTIES THERETO.

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Exhibit 99.3

Investor FAQ

Questions about the transaction

Cautionary Note Regarding Forward-Looking Statements

This communication contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding the proposed acquisition of G1 by Pharmacosmos, the expected timetable for completing the transaction, and G1’s future financial or operating performance. The words “may,” “will,” “could,” “would,” “should,” “expect,” “plan,” “anticipate,” “intend,” “believe,” “estimate,” “predict,” “project,” “potential,” “continue,” “seek,” “target” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Any forward-looking statements in this communication are based on management’s current expectations and beliefs and are subject to a number of risks, uncertainties and important factors that may cause actual events or results to differ materially from those expressed or implied by any forward-looking statements contained in this press release, including, without limitation: (i) risks associated with the timing of the closing of the proposed transaction, including the risks that a condition to closing would not be satisfied within the expected timeframe or at all or that the closing of the proposed transaction will not occur; (ii) uncertainties as to how many of G1’s stockholders will tender their shares in the offer; (iii) the possibility that a governmental entity may prohibit, delay or refuse to grant approval for the consummation of the transaction; (iv) the possibility that competing offers will be made; (v) the outcome of any legal proceedings that may be instituted against the parties and others related to the merger agreement; (vi) unanticipated difficulties or expenditures relating to the proposed transaction, the response of business partners and competitors to the announcement of the proposed transaction, and/or potential difficulties in employee retention as a result of the announcement and pendency of the proposed transaction; (vii) G1’s ability to successfully demonstrate the efficacy and safety of its drug or drug candidates, and the preclinical or clinical results for its product candidates, which may not support further development of such product candidates; (viii) comments, feedback and actions of regulatory agencies; (ix) G1’s dependence on the commercial success of COSELA (trilaciclib); (x) the inherent uncertainties associated with developing new products or technologies and operating as commercial stage company; (xi) chemotherapy shortages; and (xi) other risks identified in G1’s SEC filings, including G1’s Annual Report on Form 10-K for the year

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ended December 31, 2023, and subsequent filings with the SEC. G1 cautions you not to place undue reliance on any forward-looking statements, which speak only as of the date they are made. G1 disclaims any obligation to publicly update or revise any such statements to reflect any change in expectations or in events, conditions or circumstances on which any such statements may be based, or that may affect the likelihood that actual results will differ from those set forth in the forward-looking statements.

Additional Information and Where to Find It

The tender offer referred to in this communication has not yet commenced. This communication is for informational purposes only and is neither an offer to purchase nor a solicitation of an offer to sell shares, nor is it a substitute for the tender offer materials that Pharmacosmos and its acquisition subsidiary will file with the SEC upon commencement of the tender offer. At the time the tender offer is commenced, Pharmacosmos and its acquisition subsidiary will cause to be filed a tender offer statement on Schedule TO with the SEC, and G1 will file a solicitation/recommendation statement on Schedule 14D-9 with respect to the tender offer. THE TENDER OFFER STATEMENT (INCLUDING AN OFFER TO PURCHASE, A RELATED LETTER OF TRANSMITTAL AND OTHER OFFER DOCUMENTS) AND THE SOLICITATION/RECOMMENDATION STATEMENT WILL CONTAIN IMPORTANT INFORMATION THAT SHOULD BE READ CAREFULLY AND CONSIDERED BY G1’S STOCKHOLDERS BEFORE ANY DECISION IS MADE WITH RESPECT TO THE TENDER OFFER. Both the tender offer statement and the solicitation/recommendation statement will be mailed to G1’s stockholders free of charge. A free copy of the tender offer statement and the solicitation/recommendation statement will also be made available to all stockholders of G1 by accessing https://investor.g1therapeutics.com or by contacting Investor Relations at ir@g1therapeutics.com. In addition, the tender offer statement and the solicitation/recommendation statement (and all other documents filed with the SEC) will be available at no charge on the SEC’s website: www.sec.gov, upon filing with the SEC.

G1’S STOCKHOLDERS ARE ADVISED TO READ THE SCHEDULE TO AND THE SCHEDULE 14D-9, AS EACH MAY BE AMENDED OR SUPPLEMENTED FROM TIME TO TIME, AND ANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC WHEN THEY BECOME AVAILABLE BEFORE THEY MAKE ANY DECISION WITH RESPECT TO THE TENDER OFFER, BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT THE PROPOSED TRANSACTION AND THE PARTIES THERETO.

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Exhibit 99.4

Subject: G1 Therapeutics to be Acquired by Pharmacosmos: No 2Q24 financial conference call

Good morning,

I’m reaching out to make sure you saw this morning’s announcement that G1 has entered into a definitive agreement to be acquired by Pharmacosmos A/S, a global supportive care leader in the development of innovative treatments for patients suffering from iron deficiency and iron deficiency anemia.

This transaction will allow us to advance and accelerate our important work on behalf of patients with extensive stage small cell lung cancer with a company that shares our vision and our values. Under the terms of the agreement, Pharmacosmos will acquire all outstanding shares of G1 Therapeutics common stock for U.S. $7.15 per share in cash for a total equity value of approximately $405 million.

In light of this news, G1 will not be hosting a conference call / webcast tomorrow to discuss our second quarter 2024 financial results and business results. The Company will file a form 10-Q in the ordinary course.

Thank you, as always, for your support of G1.

Sincerely,

Will

William Roberts | Communications Officer

Vice President, Corporate Communications and Investor Relations

G1 Therapeutics, Inc.

700 Park Offices Dr. | Suite 200 | Research Triangle Park, NC 27709

(919) 907-1944 (office)

(610) 304-5882 (cell)

wroberts@g1therapeutics.com

Cautionary Note Regarding Forward-Looking Statements

This communication contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding the proposed acquisition of G1 by Pharmacosmos, the expected timetable for completing the transaction, and G1’s future financial or operating performance. The words “may,” “will,” “could,” “would,” “should,” “expect,” “plan,” “anticipate,” “intend,” “believe,” “estimate,” “predict,” “project,” “potential,” “continue,” “seek,” “target” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Any forward-looking statements in this communication are based on management’s current expectations and beliefs and are subject to a number of risks, uncertainties and important factors that may cause actual events or results to differ materially from those expressed or implied by any forward-looking statements contained in this press release, including, without limitation: (i) risks associated with the timing of the closing of the proposed transaction, including the risks that a condition to closing would not be satisfied within the expected timeframe or at all or that the closing of the proposed transaction will not occur; (ii) uncertainties as to how many of G1’s stockholders will tender their shares in the offer; (iii) the possibility that a governmental entity may prohibit, delay or refuse to grant approval for the consummation of the transaction; (iv) the possibility that competing offers will be made; (v) the outcome of any legal proceedings that may be instituted against the parties and others related to the merger agreement; (vi) unanticipated difficulties or expenditures relating to the proposed transaction, the response of business partners and competitors to the announcement of the proposed transaction, and/or potential difficulties in employee retention as a result of the announcement and pendency of the proposed transaction; (vii) G1’s ability to successfully demonstrate the efficacy and safety of its drug or drug candidates, and the preclinical or clinical results for its product candidates, which may not support further development of such product candidates; (viii) comments, feedback and actions of regulatory agencies; (ix) G1’s dependence on the commercial success of COSELA (trilaciclib); (x) the inherent uncertainties associated with developing new products or technologies and operating as commercial stage company; (xi) chemotherapy shortages; and (xii) other risks identified in G1’s SEC filings, including G1’s Annual Report on Form 10-K for the year ended December 31, 2023, and subsequent filings with the SEC. G1 cautions you not to place undue reliance on any forward-looking statements, which speak only as of the date they are made. G1 disclaims any obligation to publicly update or revise any such statements to reflect any change in expectations or in events, conditions or circumstances on which any such statements may be based, or that may affect the likelihood that actual results will differ from those set forth in the forward-looking statements.

Additional Information and Where to Find It

The tender offer referred to in this communication has not yet commenced. This communication is for informational purposes only and is neither an offer to purchase nor a solicitation of an offer to sell shares, nor is it a substitute for the tender offer materials that Pharmacosmos and its acquisition subsidiary will file with the SEC upon commencement of the tender offer. At the time the tender offer is commenced, Pharmacosmos and its acquisition subsidiary will cause to be filed a tender offer statement on Schedule TO with the SEC, and G1 will file a solicitation/recommendation statement on Schedule 14D-9 with respect to the tender offer. THE TENDER OFFER STATEMENT (INCLUDING AN OFFER TO PURCHASE, A RELATED LETTER OF TRANSMITTAL AND OTHER OFFER DOCUMENTS) AND THE SOLICITATION/RECOMMENDATION STATEMENT WILL CONTAIN IMPORTANT INFORMATION THAT SHOULD BE READ CAREFULLY AND CONSIDERED BY G1’S STOCKHOLDERS BEFORE ANY DECISION IS MADE WITH RESPECT TO THE TENDER OFFER. Both the tender offer statement and the

solicitation/recommendation statement will be mailed to G1’s stockholders free of charge. A free copy of the tender offer statement and the solicitation/recommendation statement will also be made available to all stockholders of G1 by accessing https://investor.g1therapeutics.com or by contacting Investor Relations at ir@g1therapeutics.com. In addition, the tender offer statement and the solicitation/recommendation statement (and all other documents filed with the SEC) will be available at no charge on the SEC’s website: www.sec.gov, upon filing with the SEC.

G1’S STOCKHOLDERS ARE ADVISED TO READ THE SCHEDULE TO AND THE SCHEDULE 14D-9, AS EACH MAY BE AMENDED OR SUPPLEMENTED FROM TIME TO TIME, AND ANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC WHEN THEY BECOME AVAILABLE BEFORE THEY MAKE ANY DECISION WITH RESPECT TO THE TENDER OFFER, BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT THE PROPOSED TRANSACTION AND THE PARTIES THERETO.

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Exhibit 99.5

Dear Valued Partner,

I’m reaching out to share some exciting news about G1 Therapeutics: We have reached an agreement to be acquired by Pharmacosmos, a global supportive care leader in the development of innovative treatments for patients suffering from iron deficiency and iron deficiency anemia. This combination is an important one, in that it will allow us to reach more patients who badly need our important drug COSELA^® (trilaciclib) - and therefore maximize its impact in this cancer setting - sooner and more efficiently than we could as an independent company. You can learn more about our announcement here. [link to press release]

Together, Pharmacosmos and G1 will execute on our shared vision to grow and accelerate the availability of COSELA for all appropriate patients with ES-SCLC. G1 brings a well-established and successful commercial, sales, and medical platform to Pharmacosmos, who has complementary expertise in commercializing supportive care products, a robust U.S. presence, and significant resources to maximize the penetration of COSELA into the ES-SCLC market. Together, the combined company will be able to optimize the commercial reach to oncologists across the U.S. and expand the availability of COSELA among patients living with ES-SCLC.

Today’s announcement represents an important milestone for our company and the cancer patients we seek to treat, but it is only the beginning of the process. G1 and Pharmacosmos will continue to operate as independent companies until the close of the transaction, which we expect to occur in the late third quarter of 2024. For now, it’s business as usual for us, and there are no changes to our existing contracts or relationship with you. If you have an existing relationship with Pharmacosmos, please continue to work with us as you always have.

If you have any questions, please don’t hesitate to reach out to [INSERT RELATIONSHIP OWNER NAME, TITLE]

On behalf of our entire G1 team, I’d like to thank you for your continued partnership. We value your support, appreciate your effort, and look forward to continuing to work with you as we embark on this next chapter.

Sincerely,

INSERT NAME, TITLE

Cautionary Note Regarding Forward-Looking Statements

This communication contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding the proposed acquisition of G1 by Pharmacosmos, the expected timetable for completing the transaction, and G1’s future financial or operating performance. The words “may,” “will,” “could,” “would,” “should,” “expect,” “plan,” “anticipate,” “intend,” “believe,” “estimate,” “predict,” “project,” “potential,” “continue,” “seek,” “target” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Any forward-looking statements in this communication are based on management’s current expectations and beliefs and are subject to a number of risks, uncertainties and important factors that may cause actual events or results to differ materially from those expressed or implied by any forward-looking statements contained in this press release, including, without limitation: (i) risks associated with the timing of the closing of the proposed transaction, including the risks that a condition to closing would not be satisfied within the expected timeframe or at all or that the closing of the proposed transaction will not occur; (ii) uncertainties as to how many of G1’s stockholders will tender their shares in the offer; (iii) the possibility that a governmental entity may prohibit, delay or refuse to grant approval for the consummation of the transaction; (iv) the possibility that competing offers will be made; (v) the outcome of any legal proceedings that may be instituted against the parties and others related to the merger agreement; (vi) unanticipated difficulties or expenditures relating to the proposed transaction, the response of business partners and competitors to the announcement of the proposed transaction, and/or potential difficulties in employee retention as a result of the announcement and pendency of the proposed transaction; (vii) G1’s ability to successfully demonstrate the efficacy and safety of its drug or drug candidates, and the preclinical or clinical results for its product candidates, which may not support further development of such product candidates; (viii) comments, feedback and actions of regulatory agencies; (ix) G1’s dependence on the commercial success of COSELA (trilaciclib); (x) the inherent uncertainties associated with developing new products or technologies and operating as commercial stage company; (xi) chemotherapy shortages; and (xii) other risks identified in G1’s SEC filings, including G1’s Annual Report on Form 10-K for the year ended December 31, 2023, and subsequent filings with the SEC. G1 cautions you not to place undue reliance on any forward-looking statements, which speak only as of the date they are made. G1 disclaims any obligation to publicly update or revise any such statements to reflect any change in expectations or in events, conditions or circumstances on which any such statements may be based, or that may affect the likelihood that actual results will differ from those set forth in the forward-looking statements.

Additional Information and Where to Find It

The tender offer referred to in this communication has not yet commenced. This communication is for informational purposes only and is neither an offer to purchase nor a solicitation of an offer to sell shares, nor is it a substitute for the tender offer materials that Pharmacosmos and its acquisition subsidiary will file with the SEC upon commencement of the tender offer. At the time the tender offer is commenced, Pharmacosmos and its acquisition subsidiary will cause to be filed a tender offer statement on Schedule TO with the SEC, and G1 will file a solicitation/recommendation statement on Schedule 14D-9 with respect to the tender offer. THE TENDER OFFER STATEMENT (INCLUDING AN OFFER TO PURCHASE, A RELATED LETTER OF TRANSMITTAL AND OTHER OFFER DOCUMENTS) AND THE SOLICITATION/RECOMMENDATION STATEMENT WILL CONTAIN IMPORTANT INFORMATION THAT SHOULD BE READ CAREFULLY AND CONSIDERED BY G1’S STOCKHOLDERS BEFORE ANY DECISION IS MADE WITH RESPECT TO THE TENDER OFFER. Both the tender offer statement and the

solicitation/recommendation statement will be mailed to G1’s stockholders free of charge. A free copy of the tender offer statement and the solicitation/recommendation statement will also be made available to all stockholders of G1 by accessing https://investor.g1therapeutics.com or by contacting Investor Relations at ir@g1therapeutics.com. In addition, the tender offer statement and the solicitation/recommendation statement (and all other documents filed with the SEC) will be available at no charge on the SEC’s website: www.sec.gov, upon filing with the SEC.

G1’S STOCKHOLDERS ARE ADVISED TO READ THE SCHEDULE TO AND THE SCHEDULE 14D-9, AS EACH MAY BE AMENDED OR SUPPLEMENTED FROM TIME TO TIME, AND ANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC WHEN THEY BECOME AVAILABLE BEFORE THEY MAKE ANY DECISION WITH RESPECT TO THE TENDER OFFER, BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT THE PROPOSED TRANSACTION AND THE PARTIES THERETO.

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Exhibit 99.6

[The following post was made available by G1 Therapeutics, Inc. on X (formerly known as Twitter).]

We are excited to announce that G1 has entered into an agreement to be acquired by Pharmacosmos to maximize the global availability of our myeloprotection drug among patients living with extensive stage small cell #lungcancer. Learn more: bit.ly/46zgk1H

Cautionary Note Regarding Forward-Looking Statements

This communication contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding the proposed acquisition of G1 by Pharmacosmos, the expected timetable for completing the transaction, and G1’s future financial or operating performance. The words “may,” “will,” “could,” “would,” “should,” “expect,” “plan,” “anticipate,” “intend,” “believe,” “estimate,” “predict,” “project,” “potential,” “continue,” “seek,” “target” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Any forward-looking statements in this communication are based on management’s current expectations and beliefs and are subject to a number of risks, uncertainties and important factors that may cause actual events or results to differ materially from those expressed or implied by any forward-looking statements contained in this press release, including, without limitation: (i) risks associated with the timing of the closing of the proposed transaction, including the risks that a condition to closing would not be satisfied within the expected timeframe or at all or that the closing of the proposed transaction will not occur; (ii) uncertainties as to how many of G1’s stockholders will tender their shares in the offer; (iii) the possibility that a governmental entity may prohibit, delay or refuse to grant approval for the consummation of the transaction; (iv) the possibility that competing offers will be made; (v) the outcome

of any legal proceedings that may be instituted against the parties and others related to the merger agreement; (vi) unanticipated difficulties or expenditures relating to the proposed transaction, the response of business partners and competitors to the announcement of the proposed transaction, and/or potential difficulties in employee retention as a result of the announcement and pendency of the proposed transaction; (vii) G1’s ability to successfully demonstrate the efficacy and safety of its drug or drug candidates, and the preclinical or clinical results for its product candidates, which may not support further development of such product candidates; (viii) comments, feedback and actions of regulatory agencies; (ix) G1’s dependence on the commercial success of COSELA (trilaciclib); (x) the inherent uncertainties associated with developing new products or technologies and operating as commercial stage company; (xi) chemotherapy shortages; and (xii) other risks identified in G1’s SEC filings, including G1’s Annual Report on Form 10-K for the year ended December 31, 2023, and subsequent filings with the SEC. G1 cautions you not to place undue reliance on any forward-looking statements, which speak only as of the date they are made. G1 disclaims any obligation to publicly update or revise any such statements to reflect any change in expectations or in events, conditions or circumstances on which any such statements may be based, or that may affect the likelihood that actual results will differ from those set forth in the forward-looking statements.

Additional Information and Where to Find It

The tender offer referred to in this communication has not yet commenced. This communication is for informational purposes only and is neither an offer to purchase nor a solicitation of an offer to sell shares, nor is it a substitute for the tender offer materials that Pharmacosmos and its acquisition subsidiary will file with the SEC upon commencement of the tender offer. At the time the tender offer is commenced, Pharmacosmos and its acquisition subsidiary will cause to be filed a tender offer statement on Schedule TO with the SEC, and G1 will file a solicitation/recommendation statement on Schedule 14D-9 with respect to the tender offer. THE TENDER OFFER STATEMENT (INCLUDING AN OFFER TO PURCHASE, A RELATED LETTER OF TRANSMITTAL AND OTHER OFFER DOCUMENTS) AND THE SOLICITATION/RECOMMENDATION STATEMENT WILL CONTAIN IMPORTANT INFORMATION THAT SHOULD BE READ CAREFULLY AND CONSIDERED BY G1’S STOCKHOLDERS BEFORE ANY DECISION IS MADE WITH RESPECT TO THE TENDER OFFER. Both the tender offer statement and the solicitation/recommendation statement will be mailed to G1’s stockholders free of charge. A free copy of the tender offer statement and the solicitation/recommendation statement will also be made available to all stockholders of G1 by accessing https://investor.g1therapeutics.com or by contacting Investor Relations at ir@g1therapeutics.com. In addition, the tender offer statement and the solicitation/recommendation statement (and all other documents filed with the SEC) will be available at no charge on the SEC’s website: www.sec.gov, upon filing with the SEC.

G1’S STOCKHOLDERS ARE ADVISED TO READ THE SCHEDULE TO AND THE SCHEDULE 14D-9, AS EACH MAY BE AMENDED OR SUPPLEMENTED FROM TIME TO TIME, AND ANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC WHEN THEY BECOME AVAILABLE BEFORE THEY MAKE ANY DECISION WITH RESPECT TO THE TENDER OFFER, BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT THE PROPOSED TRANSACTION AND THE PARTIES THERETO.

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Exhibit 99.7

[The following communication was made available by G1 Therapeutics, Inc. on LinkedIn.]

We are excited to announce that G1 has entered into a definitive agreement to be acquired by @Pharmacosmos for approximately $405 million. The combined company will be able to optimize the commercial reach to oncologists and expand the availability of our myeloprotection drug among patients living with ES-SCLC.

G1 brings a well-established and successful commercial, sales, and medical platform to Pharmacosmos, who has complementary expertise in commercializing hematology and supportive care products a robust global commercial presence.

For more information, please read our press release and other important information regarding the proposed transaction here: bit.ly/46zgk1H

Cautionary Note Regarding Forward Looking Statements

This communication contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding the proposed acquisition of G1 by Pharmacosmos, the expected timetable for completing the transaction, and G1’s future financial or operating performance. The words “may,” “will,” “could,” “would,” “should,” “expect,” “plan,” “anticipate,” “intend,” “believe,” “estimate,” “predict,” “project,” “potential,” “continue,” “seek,” “target” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Any forward-looking statements in this communication are based on management’s current expectations and beliefs and are subject to a number of risks, uncertainties and important factors that may cause actual events or results to differ materially from those expressed or implied by any forward-looking statements contained in this press release, including, without limitation: (i) risks associated with the timing of the closing of the proposed transaction, including the risks that a condition to closing would not be satisfied within the

expected timeframe or at all or that the closing of the proposed transaction will not occur; (ii) uncertainties as to how many of G1’s stockholders will tender their shares in the offer; (iii) the possibility that a governmental entity may prohibit, delay or refuse to grant approval for the consummation of the transaction; (iv) the possibility that competing offers will be made; (v) the outcome of any legal proceedings that may be instituted against the parties and others related to the merger agreement; (vi) unanticipated difficulties or expenditures relating to the proposed transaction, the response of business partners and competitors to the announcement of the proposed transaction, and/or potential difficulties in employee retention as a result of the announcement and pendency of the proposed transaction; (vii) G1’s ability to successfully demonstrate the efficacy and safety of its drug or drug candidates, and the preclinical or clinical results for its product candidates, which may not support further development of such product candidates; (viii) comments, feedback and actions of regulatory agencies; (ix) G1’s dependence on the commercial success of COSELA (trilaciclib); (x) the inherent uncertainties associated with developing new products or technologies and operating as commercial stage company; (xi) chemotherapy shortages; and (xii) other risks identified in G1’s SEC filings, including G1’s Annual Report on Form 10-K for the year ended December 31, 2023, and subsequent filings with the SEC. G1 cautions you not to place undue reliance on any forward-looking statements, which speak only as of the date they are made. G1 disclaims any obligation to publicly update or revise any such statements to reflect any change in expectations or in events, conditions or circumstances on which any such statements may be based, or that may affect the likelihood that actual results will differ from those set forth in the forward-looking statements.

Additional Information and Where to Find It

The tender offer referred to in this communication has not yet commenced. This communication is for informational purposes only and is neither an offer to purchase nor a solicitation of an offer to sell shares, nor is it a substitute for the tender offer materials that Pharmacosmos and its acquisition subsidiary will file with the SEC upon commencement of the tender offer. At the time the tender offer is commenced, Pharmacosmos and its acquisition subsidiary will cause to be filed a tender offer statement on Schedule TO with the SEC, and G1 will file a solicitation/recommendation statement on Schedule 14D-9 with respect to the tender offer. THE TENDER OFFER STATEMENT (INCLUDING AN OFFER TO PURCHASE, A RELATED LETTER OF TRANSMITTAL AND OTHER OFFER DOCUMENTS) AND THE SOLICITATION/RECOMMENDATION STATEMENT WILL CONTAIN IMPORTANT INFORMATION THAT SHOULD BE READ CAREFULLY AND CONSIDERED BY G1’S STOCKHOLDERS BEFORE ANY DECISION IS MADE WITH RESPECT TO THE TENDER OFFER. Both the tender offer statement and the solicitation/recommendation statement will be mailed to G1’s stockholders free of charge. A free copy of the tender offer statement and the solicitation/recommendation statement will also be made available to all stockholders of G1 by accessing https://investor.g1therapeutics.com or by contacting Investor Relations at ir@g1therapeutics.com. In addition, the tender offer statement and the solicitation/recommendation statement (and all other documents filed with the SEC) will be available at no charge on the SEC’s website: www.sec.gov, upon filing with the SEC.

G1’S STOCKHOLDERS ARE ADVISED TO READ THE SCHEDULE TO AND THE SCHEDULE 14D-9, AS EACH MAY BE AMENDED OR SUPPLEMENTED FROM TIME TO TIME, AND ANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC WHEN THEY BECOME AVAILABLE BEFORE THEY MAKE ANY DECISION WITH RESPECT TO THE TENDER OFFER, BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT THE PROPOSED TRANSACTION AND THE PARTIES THERETO.

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Exhibit 99.8

Dear [Partner],

I just wanted to reach out and personally make you aware of the transaction we announced this morning given our strong existing partnership. We look forward to continuing to work closely together on optimizing the value of our portfolio for patients. We believe this transaction puts us in a stronger place to achieve those objectives. On behalf of our entire G1 team, I’d like to thank you for your continued partnership. We value your support, appreciate your effort, and look forward to continuing to work with you as we embark on this next chapter. Please see the few summary points we have been sharing with our most important partners.

We have reached an agreement to be acquired by Pharmacosmos, a global hematology and supportive care leader in the development of innovative treatments for patients suffering from iron deficiency and iron deficiency anemia. This combination is an important one, in that it will allow us to reach more patients who badly need our important drug COSELA^® (trilaciclib) - and therefore maximize its impact in this cancer setting - sooner and more efficiently than we could as an independent company. You can learn more about our announcement here. [link to press release]

Together, Pharmacosmos and G1 will execute on the shared vision to grow and accelerate the availability of COSELA for all appropriate patients with ES-SCLC. G1 brings a well-established and successful commercial, sales, and medical platform to Pharmacosmos, who has complementary expertise in commercializing supportive care products, a robust global commercial presence with a portfolio of important products, and significant resources to maximize the penetration of COSELA into the ES-SCLC market. Together, the combined company will be able to optimize the commercial reach to oncologists and expand the availability of COSELA among patients living with ES-SCLC.

Today’s announcement represents an important milestone for our company and the cancer patients we seek to treat, but it is only the beginning of the process. G1 and Pharmacosmos will continue to operate as independent companies until the close of the transaction, which we expect to occur late in the third quarter of 2024. For now, it’s business as usual for us, so there are no changes to our existing partnership.

If you have any questions, please don’t hesitate to reach out to me.

Sincerely,

Jack Bailey

CEO

Forward-Looking Statements

This document contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, statements regarding the proposed acquisition of G1 by Pharmacosmos, the expected timetable for completing the transaction, and G1’s future financial or operating performance. The words “may,” “will,” “could,” “would,” “should,” “expect,” “plan,” “anticipate,” “intend,” “believe,” “estimate,” “predict,” “project,” “potential,” “continue,” “seek,” “target” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Any forward-looking statements in this document are based on management’s current expectations and beliefs and are subject to a number of risks, uncertainties and important factors that may cause actual events or results to differ materially from those expressed or implied by any forward-looking statements contained in this press release, including, without limitation: (i) risks associated with the timing of the closing of the proposed transaction, including the risks that a condition to closing would not be satisfied within the expected timeframe or at all or that the closing of the proposed transaction will not occur; (ii) uncertainties as to how many of G1’s stockholders will tender their shares in the offer; (iii) the possibility that a governmental entity may prohibit, delay or refuse to grant approval for the consummation of the transaction; (iv) the possibility that competing offers will be made; (v) the outcome of any legal proceedings that may be instituted against the parties and others related to the merger agreement; (vi) unanticipated difficulties or expenditures relating to the proposed transaction, the response of business partners and competitors to the announcement of the proposed transaction, and/or potential difficulties in employee retention as a result of the announcement and pendency of the proposed transaction; (vii) G1’s ability to successfully demonstrate the efficacy and safety of its drug or drug candidates, and the preclinical or clinical results for its product candidates, which may not support further development of such product candidates; (viii) comments, feedback and actions of regulatory agencies; (ix) G1’s dependence on the commercial success of COSELA (trilaciclib); (x) the inherent uncertainties associated with developing new products or technologies and operating as commercial stage company; (xi) chemotherapy shortages; and (xii) other risks identified in G1’s SEC filings, including G1’s Annual Report on Form 10-K for the year ended December 31, 2023, and subsequent filings with the SEC. G1 cautions you not to place undue reliance on any forward-looking statements, which speak only as of the date they are made. G1 disclaims any obligation to publicly update or revise any such statements to reflect any change in expectations or in events, conditions or circumstances on which any such statements may be based, or that may affect the likelihood that actual results will differ from those set forth in the forward-looking statements.

Additional Information and Where to Find It

The tender offer referred to in this document has not yet commenced. This document is for informational purposes only and is neither an offer to purchase nor a solicitation of an offer to sell shares, nor is it a substitute for the tender offer materials that Pharmacosmos and its acquisition subsidiary will file with the SEC upon commencement of the tender offer. At the time the tender offer is commenced, Potomac and its acquisition subsidiary will cause to be filed a tender offer statement on Schedule TO with the SEC, and G1 will file a solicitation/recommendation statement on Schedule 14D-9 with respect to the tender offer.

THE TENDER OFFER STATEMENT (INCLUDING AN OFFER TO PURCHASE, A RELATED LETTER OF TRANSMITTAL AND OTHER OFFER DOCUMENTS) AND THE SOLICITATION/RECOMMENDATION STATEMENT WILL CONTAIN IMPORTANT INFORMATION THAT SHOULD BE READ CAREFULLY AND CONSIDERED BY G1’S STOCKHOLDERS BEFORE ANY DECISION IS MADE WITH RESPECT TO THE TENDER OFFER. Both the tender offer statement and the solicitation/recommendation statement will be mailed to G1’s stockholders free of charge. A free copy of the tender offer statement and the solicitation/recommendation statement will also be made available to all stockholders of G1 by accessing https://investor.g1therapeutics.com/ or by contacting Investor Relations at ir@g1therapeutics.com. In addition, the tender offer statement and the solicitation/recommendation statement (and all other documents filed with the SEC) will be available at no charge on the SEC’s website: www.sec.gov, upon filing with the SEC.

G1’S STOCKHOLDERS ARE ADVISED TO READ THE SCHEDULE TO AND THE SCHEDULE 14D-9, AS EACH MAY BE AMENDED OR SUPPLEMENTED FROM TIME TO TIME, AND ANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC WHEN THEY BECOME AVAILABLE BEFORE THEY MAKE ANY DECISION WITH RESPECT TO THE TENDER OFFER, BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT THE PROPOSED TRANSACTION AND THE PARTIES THERETO.

2