1.

To approve, in accordance with Nasdaq Listing Rule 5635(d), the issuance of shares of the Company’s common stock, par value $0.0001 per share (“Common Stock”), upon conversion of the Company’s Series B Non-Voting Convertible Preferred Stock, par value $0.0001 per share (“Series B Preferred Stock”) (the “Conversion Proposal” or “Proposal No. 1”); and

2.

To approve the adjournment or postponement of the Special Meeting, if necessary, to continue to solicit votes for Proposal No. 1 (the “Adjournment Proposal” or “Proposal No. 2”).

1.

In accordance with Nasdaq Listing Rule 5635(d), the issuance of shares of the Company’s common stock, par value $0.0001 per share (“Common Stock”), upon conversion of the Company’s Series B Non-Voting Convertible Preferred Stock, par value $0.0001 per share (“Series B Preferred Stock”) (the “Conversion Proposal” or “Proposal No. 1”); and

2.

The adjournment or postponement of the Special Meeting, if necessary, to continue to solicit votes for Proposal No. 1 (the “Adjournment Proposal” or “Proposal No. 2”).

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by Telephone - You can vote by telephone by calling 1-800-690-6903 and following the instructions on the proxy card;

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by Internet - You can vote over the Internet at www.proxyvote.com by following the instructions on the proxy card;

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by Mail - You can vote by mail by signing, dating and mailing the proxy card, which you may have received by mail; or

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Electronically at the Meeting - You may vote at the Special Meeting by visiting www.virtualshareholdermeeting.com/RNAC2024SM2 and entering the 16-digit control number included on your proxy card or on the instructions that accompanied your proxy materials. The meeting webcast will begin promptly at 10:00 a.m., Eastern Time, on September 20, 2024.

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by submitting a duly executed proxy bearing a later date;

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by granting a subsequent proxy through the Internet or telephone;

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by giving written notice of revocation to the Secretary of the Company prior to the Special Meeting; or

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by voting electronically at the virtual Special Meeting.

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Proposal No. 1 - Approval of, in accordance with Nasdaq Listing Rule 5635(d), the issuance of the Company’s Common Stock, upon conversion of the Company’s Series B Preferred Stock; and

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Proposal No. 2 - To approve the adjournment or postponement of the Special Meeting, if necessary, to continue to solicit votes for Proposal No. 1.

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Proposal No. 1 - The affirmative vote of the holders of shares of Common Stock representing a majority of the votes cast on the matter is required for the approval of Proposal No. 1, subject to the separate tabulation of votes described in “Questions and Answers About the Special Meeting—How many votes can be cast by all stockholders?” set forth above. Broker non-votes (if any) and abstentions will not be counted as votes cast on the matter and will have no effect on the outcome of this proposal.

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Proposal No. 2 - If a quorum is present at the Special Meeting, the affirmative vote of the holders of shares of Common Stock representing a majority of the votes cast on the matter is required for the approval of Proposal No. 2. If a quorum is not present at the Special Meeting, the affirmative vote of the holders of a majority of the shares of Common Stock present at the Special Meeting or represented by proxy is required for the approval of Proposal No. 2.

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Proposal No. 1 - FOR the approval of Proposal No. 1.

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Proposal No. 2 - FOR the approval of Proposal No. 2.

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Dr. Timothy A. Springer, Ph.D., a member of our Board of Directors, purchased 1,636,832 shares of Series B Preferred Stock in the Private Placement at the Private Placement purchase price per share of $20, for a purchase price of $32,736,640. Additionally, TAS Partners LLC, an affiliate of Dr. Springer, and Dr. Chafen Lu, Ph.D., Dr. Springer’s spouse, purchased 721,361 and 1,307 shares of Series B Preferred Stock, respectively, in the Private Placement, for purchase prices of $14,427,220 and $26,140, respectively. If stockholders do not ever approve the issuance of Common Stock underlying these shares of Series B Preferred Stock, these shares will be unable to convert into Common Stock and may have little value.

*

Represents beneficial ownership of less than one percent.

(1)

Based on a Schedule 13D/A filed with the SEC on July 5, 2024 and other information known to us, consists of (i) 4,373,966 shares of Common Stock held directly by Timothy A. Springer, Ph.D., a member of our Board of Directors, (ii) 1,636,832 shares of Common Stock issuable upon conversion of shares of Series B Preferred Stock held directly by Timothy A. Springer, Ph.D., (iii) 1,688 shares of Common Stock issuable upon exercise of outstanding options within 60 days of July 29, 2024 and held directly by Timothy A. Springer, Ph.D., (iv) 1,927,630 shares of Common Stock held by TAS Partners LLC (“TAS”) directly, (v) 721,361 shares of Common Stock issuable upon conversion of shares of Series B Preferred Stock held by TAS directly, (vi) 167,040 shares of Common Stock issuable upon exercise of underlying warrants exercisable within 60 days of July 29, 2024 held by TAS directly, (vii) 3,493 shares of Common Stock held by Dr. Chafen Lu, Dr. Springer’s wife, and (viii) 1,307 shares of Common Stock issuable upon conversion of shares of Series B Preferred Stock held by Dr. Chafen Lu. Dr. Springer is the sole managing member of TAS. Dr. Springer exercises sole voting and dispositive power over the shares held by him directly and the shares held by TAS. Dr. Springer disclaims beneficial ownership of the shares held by TAS. Dr. Lu exercises sole voting and dispositive power over the shares held by her directly. The principal business address of each of Dr. Springer, TAS, and Dr. Lu is 36 Woodman Road, Newton, MA, 02467.

(2)

Based on a Schedule 13D/A filed with the SEC on April 10, 2024 and other information known to us, consists of (i) 500,444 shares of Common Stock held directly by Murat Kalayoglu, M.D., Ph.D., a member of our Board of Directors, (ii) 1,688 shares of Common Stock issuable upon exercise of outstanding options within 60 days of July 29, 2024 and held directly by Murat Kalayoglu, M.D., Ph.D., (iii) 3,036,887 shares of Common Stock held by Seven One Eight Three Four Irrevocable Trust directly, and (iv) up to 3,398,448 shares of Common Stock issuable upon conversion of shares of Series A Preferred Stock held by Seven One Eight Three Four Irrevocable Trust. The trustees of Seven One Eight Three Four Irrevocable Trust are Elizabeth Hoge and Sinan Kalayoglu, each of whom has shared voting and dispositive control over the shares of Common Stock and Series A Preferred Stock held by Seven One Eight Three Four Irrevocable Trust. Dr. Kalayoglu has the power to remove and appoint new trustees of Seven One Eight Three Four Irrevocable Trust and, pursuant to a right of substitution, to acquire from Seven One Eight Three Four Irrevocable Trust the shares of Common Stock and Series A Preferred Stock held by Seven One Eight Three Four Irrevocable Trust in exchange for assets with an equal value to such shares. Accordingly, Dr. Kalayoglu may be deemed to have sole voting and dispositive power of the shares of Common Stock and Series A Preferred Stock held by Seven One Eight Three Four Irrevocable Trust. The ability of the shares of Series A Preferred Stock held by Dr. Kalayoglu and Seven One Eight Three Four Irrevocable Trust to convert into shares of Common Stock is subject to a beneficial ownership limitation, such that neither Dr. Kalayoglu nor Seven One Eight Three Four Irrevocable Trust may convert shares of Series A Preferred Stock into Common Stock to the extent that doing so would result in such holder beneficially owning greater than 19.9% of the Company’s outstanding Common Stock after giving effect to such conversion. Accordingly, the numbers of shares of Common Stock presented in this row include only a total of 1,536,731 shares of Common Stock issuable upon conversion of the shares of Series A Preferred Stock held by Seven One Eight Three Four Irrevocable Trust, and assume Seven One Eight Three Four Irrevocable Trust does not convert any shares of Series A Preferred Stock beyond such limitation.

(3)

Based on a Schedule 13G/A filed with the SEC on May 10, 2024 and other information known to us, consists of 2,708,422 shares of Common Stock owned by funds or accounts managed by direct or indirect subsidiaries of FMR LLC, all of which shares are beneficially owned, or may be deemed to be beneficially owned, by FMR LLC, certain of its subsidiaries and affiliates, and other companies. Abigail P. Johnson is a Director, the Chairman and the Chief Executive Officer of FMR LLC. Members of the Johnson family, including Abigail P. Johnson, are the predominant owners, directly or through trusts, of Series B voting common shares of FMR LLC, representing 49% of the voting power of FMR LLC. The Johnson family group and all other Series B shareholders have entered into a shareholders’ voting agreement under which all Series B voting common shares will be voted in accordance with the majority vote of Series B voting common shares. Accordingly, through their ownership of voting common shares and the execution of the shareholders’ voting agreement, members of the Johnson family may be deemed, under the Investment Company Act of 1940, to form a controlling group with respect to FMR LLC. The address of these funds and accounts is 245 Summer Street, Boston, MA 02210.

(4)

Consists of 8,731 shares of Common Stock held by Dr. Brunn directly.

(5)

Consists of 117,297 shares of Common Stock underlying outstanding stock options exercisable within 60 days of July 29, 2024 held by Dr. Jewell directly.

(6)

Consists of 235,201 shares of Common Stock underlying outstanding stock options exercisable within 60 days of July 29, 2024 held by Dr. Kurtoglu directly.

(7)

Consists of 5,301 shares of Common Stock held by Dr. Traber directly. Dr. Traber ceased service as our Chief Medical Officer effective November 13, 2023 and ceased full-time employment with the Company effective December 31, 2023.

(8)

Consists of 2,983 shares of Common Stock held by Dr. Johnston directly. Dr. Johnston ceased service as our Chief Operations Officer effective November 13, 2023 and ceased full-time employment with the Company effective December 31, 2023.

(9)

Consists of (i) 7,096 shares of Common Stock held by Ms. Cox directly, (ii) 1,094 shares of Common Stock issuable upon exercise of underlying warrants exercisable within 60 days of July 29, 2024, and (iii) 1,836 shares of Common Stock underlying outstanding stock options exercisable within 60 days of July 29, 2024.

(10)

We are not aware of any beneficial ownership of Common Stock by Dr. Ando, who retired from the Board of Directors on January 4, 2023.

(11)

Consists of (i) 8,333 shares of Common Stock held by Mr. Barabe directly and (ii) 1,688 shares of Common Stock underlying outstanding stock options exercisable within 60 days of July 29, 2024.

(12)

Consists of (i) 233 shares of Common Stock held by Dr. de Silva directly and (ii) 1,688 shares of Common Stock underlying outstanding stock options exercisable within 60 days of July 29, 2024.

(13)

Consists of 422 shares of Common Stock underlying outstanding stock options exercisable within 60 days of July 29, 2024 held by Dr. Malik directly.

(14)

Consists of (i) 2,694 shares of Common Stock held by Mr. Myers directly and (ii) 656 shares of Common Stock issuable upon exercise of underlying warrants exercisable within 60 days of July 29, 2024. Mr. Myers resigned from the Board of Directors on November 21, 2023.

(15)

We are not aware of any beneficial ownership of Common Stock by Mr. Sallin directly. Mr. Sallin resigned from the Board of Directors on February 28, 2024.

(16)

Based on a Schedule 13D/A filed with the SEC on April 10, 2024 and other information known to us, consists of (i) 113,821 shares of Common Stock held by Dr. Singer directly, (ii) 383,796 shares of Common Stock held by Thirsty Brook 2010 Irrevocable Trust, a trust for which Dr. Singer is a trustee, that Dr. Singer has the right to acquire pursuant to a right of substitution in exchange for assets with an equal value to such shares, (iii) 56,719 shares of Common Stock held by Singer Asefzadeh Family Holding Trust, a trust for which Dr. Singer is a trustee and beneficiary, (iv) 7,127 shares of Common Stock held by Bakezilla 2019 Irrevocable Trust, a trust for which Dr. Singer is a trustee and beneficiary, (v) 14,788 shares of Common Stock held by Dr. Baharak Asefzadeh, Dr. Singer’s spouse, (vi) 96,219 shares of Common Stock held by a minor child of Dr. Singer through a custodial account established pursuant to the Uniform Transfer to Minors Act (“UTMA”) for which Dr. Singer serves as custodian, (vii) 96,219 shares of Common Stock held by a minor child of Dr. Singer through a custodial account established pursuant to the UTMA for which Dr. Singer serves as custodian, and (viii) 1,688 shares of Common Stock issuable upon exercise of outstanding options within 60 days of July 29, 2024 held by Dr. Singer directly.

(17)

Consists of 1,841 shares of Common Stock held by Mr. Zenner directly and (ii) 1,688 shares of Common Stock underlying outstanding stock options exercisable within 60 days of July 29, 2024.

(18)

Includes (i) 10,645,627 shares of Common Stock owned directly or beneficially by our executive officers or members of our Board of Directors, (ii) 533,018 shares of Common Stock underlying outstanding stock options and warrants exercisable within 60 days of July 29, 2024, (iii) 1,536,731 shares of Common Stock issuable upon conversion of the shares of Series A Preferred Stock, and (iv) 2,359,500 shares of Common Stock issuable upon conversion of shares of Series B Preferred Stock.