Exhibit
10.3


 


September
14, 2021


 


Aesther
Healthcare Acquisition Corp.





515
Madison Avenue, Suite 8078


New
York, New York 10022


 


Re:
Initial Public Offering


 


Ladies
and Gentlemen:


 


This
letter (this “Letter Agreement”) is being delivered to you in accordance with the Underwriting Agreement (the “Underwriting
Agreement”) to be entered into by and between Aesther Healthcare Acquisition Corp., a Delaware corporation (the “Company”)
and EF Hutton, division of Benchmark Investments, LLC, as representative of the underwriters (each, an “Underwriter”
and collectively, the “Underwriters”), relating to an underwritten initial public offering (the “Public Offering”),
of up to 11,500,000 of the Company’s units (including up to 1,500,000 units that may be purchased to cover over-allotments, if
any) (the “Units”), each comprised of one share of the Company’s Class A common stock, par value $0.0001 per
share (the “Common Stock”), and one-half of one redeemable warrant. Each whole warrant (each, a “Warrant”)
entitles the holder thereof to purchase one share of Common Stock at a price of $11.50 per share, subject to adjustment. The Units will
be sold in the Public Offering pursuant to a registration statement on Form S-1 (File No. 333-258012) and prospectus (the “Prospectus”)
filed by the Company with the U.S. Securities and Exchange Commission (the “Commission”) and the Company has applied
to have the Units listed on the Nasdaq Global Market. Certain capitalized terms used herein are defined in paragraph 11 hereof.


 


In
order to induce the Company and the Underwriters to enter into the Underwriting Agreement and to proceed with the Public Offering and
for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, Aesther Healthcare Sponsor,
LLC (the “Sponsor”) and each of the undersigned individuals, each of whom is a member of the Company’s board
of directors and/or management team or an advisor of the Company (each, an “Insider” and collectively, the “Insiders”),
hereby agrees with the Company as follows:


 


1.
The Sponsor and each Insider agrees that if the Company seeks stockholder approval of a proposed Business Combination, then in
connection with such proposed Business Combination, it, he or she shall (i) vote any shares of Capital Stock owned by it, him or her
in favor of any proposed Business Combination and (ii) not redeem any shares of Common Stock owned by it, him or her in connection
with such stockholder approval. If the Company engages in a tender offer in connection with any proposed Business Combination, the
Sponsor and each Insider agrees that it, he or she will not seek to sell its, his or her shares of Common Stock to the Company in
connection with such tender offer.


 




    	 



     


    

 


2. The
Sponsor and each Insider hereby agrees that in the event that the Company fails to consummate a Business Combination within 12 months
from the closing of the Public Offering (or up to 18 months if the Company extended such period in accordance with the Company’s
amended and restated certificate of incorporation (the “Charter”)) or such later period approved by the Company’s
stockholders in accordance with the Company’s Charter, the Sponsor and each Insider shall take all reasonable steps to cause the
Company to (i) cease all operations except for the purpose of winding up, (ii) as promptly as reasonably possible but not more than 10
business days thereafter, subject to lawfully available funds therefor, redeem 100% of the Common Stock sold as part of the Units in
the Public Offering (the “Offering Shares”), at a per-share price, payable in cash, equal to the aggregate amount
then on deposit in the Trust Account, including interest earned on the funds held in the Trust Account and not previously released to
the Company to pay its taxes (less up to $100,000 of interest to pay dissolution expenses), divided by the number of then outstanding
Offering Shares, which redemption will completely extinguish all Public Stockholders’ rights as stockholders of the Company (including
the right to receive further liquidation distributions, if any), subject to applicable law, and (iii) as promptly as reasonably possible
following such redemption, subject to the approval of the Company’s remaining stockholders and the Company’s board of directors,
dissolve and liquidate, subject in each case to the Company’s obligations under Delaware law to provide for claims of creditors
and other requirements of applicable law. The Sponsor and each Insider agree not to propose any amendment to the Company’s amended
and restated certificate of incorporation that would modify (i) the substance or timing of the Company’s obligation to redeem 100%
of the Offering Shares if the Company does not complete a Business Combination within 12 months from the closing of the Public Offering
(or up to 18 months if the Company extended such period in accordance with the Company’s Charter) or (ii) the other provisions
relating to stockholders’ rights or pre-initial business combination activities, unless the Company provides its Public Stockholders
with the opportunity to redeem their Offering Shares upon approval of any such amendment at a per-share price, payable in cash, equal
to the aggregate amount then on deposit in the Trust Account, including interest (which interest shall be net of amounts released for
payment of taxes) divided by the number of then outstanding Offering Shares. The Sponsor and each Insider agree to waive its redemption
rights with respect to shares of Capital Stock owned by it in connection with a stockholder vote to approve an amendment to the Company’s
amended and restated certificate of incorporation (A) to modify the substance or timing of the Company’s obligation to redeem 100%
of the Offering Shares if the Company does not complete a Business Combination within 12 months from the closing of the Public Offering
(or up to 18 months if the Company extended such period in accordance with the Company’s Charter) or (B) with respect to any other
provision relating to stockholders’ rights or pre-initial business combination activity.


 


Each
of the Sponsor and each Insider acknowledges that it, he or she has no right, title, interest or claim of any kind in or to any monies
held in the Trust Account or any other asset of the Company as a result of any liquidation of the Company with respect to the Founder
Shares held by it, him or her. The Sponsor and each Insider hereby further waives, with respect to any shares of Common Stock held by
it, him or her, if any, whether acquired now or hereafter, any redemption rights it, he or she may have in connection with the consummation
of a Business Combination, including, without limitation, any such rights available in the context of a stockholder vote to approve such
Business Combination or a stockholder vote to approve an amendment to the amended and restated certificate of incorporation to modify
(i) (A) the substance or timing of the Company’s obligation to redeem 100% of the Offering Shares if the Company has not consummated
a Business Combination within the time period set forth in the amended and restated certificate of incorporation or (B) any other provisions
relating to stockholders’ rights or pre-initial Business Combination activity or (ii) in the context of a tender offer made by
the Company to purchase shares of Common Stock (although the Sponsor, the Insiders and their respective affiliates shall be entitled
to redemption and liquidation rights with respect to any Offering Shares it or they hold if the Company fails to consummate a Business
Combination within 12 months from the date of the closing of the Public Offering (or up to 18 months if the Company extended such period
in accordance with the Company’s Charter)).


 




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3. During
the period commencing on the effective date of the Underwriting Agreement and ending 180 days after such date, the Sponsor and each Insider
shall not, without the prior written consent of the Representative, (i) sell, offer to sell, contract or agree to sell, hypothecate,
pledge, grant any option to purchase or otherwise dispose of or agree to dispose of, directly or indirectly, or establish or increase
a put equivalent position or liquidate or decrease a call equivalent position within the meaning of Section 16 of the Securities Exchange
Act of 1934, as amended (the “Exchange Act”), and the rules and regulations of the Commission promulgated thereunder,
with respect to any Units, shares of Capital Stock, Warrants or any securities convertible into, or exercisable, or exchangeable for,
shares of Capital Stock owned by it, him or her, (ii) enter into any swap or other arrangement that transfers to another, in whole or
in part, any of the economic consequences of ownership of any Units, shares of Capital Stock, Warrants or any securities convertible
into, or exercisable, or exchangeable for, shares of Capital Stock owned by it, him or her, whether any such transaction is to be settled
by delivery of such securities, in cash or otherwise, or (iii) publicly announce any intention to effect any transaction specified in
clause (i) or (ii). Each of the Insiders and the Sponsor acknowledges and agrees that, prior to the effective date of any release or
waiver, of the restrictions set forth in this paragraph 3 or paragraph 7 below, the Company shall announce the impending release or waiver
by press release through a major news service at least two business days before the effective date of the release or waiver. Any release
or waiver granted shall only be effective two business days after the publication date of such press release. The provisions of this
paragraph will not apply if the release or waiver is effected solely to permit a transfer not for consideration and the transferee has
agreed in writing to be bound by the same terms described in this Letter Agreement to the extent and for the duration that such terms
remain in effect at the time of the transfer.


 


4. In
the event of the liquidation of the Trust Account upon the failure of the Company to consummate its initial Business Combination within
the time period set forth in the amended and restated certificate of incorporation, as amended, the Sponsor (which for purposes of clarification
shall not extend to any other stockholders, members or managers of the Sponsor) agrees to indemnify and hold harmless the Company against
any and all loss, liability, claim, damage and expense whatsoever (including, but not limited to, any and all legal or other expenses
reasonably incurred in investigating, preparing or defending against any litigation, whether pending or threatened, or any claim whatsoever)
to which the Company may become subject as a result of any claim by (i) any third party (other than the Company’s independent accountants)
for services rendered or products sold to the Company or (ii) a prospective target business with which the Company has entered into a
letter of intent, confidentiality or other similar agreement for a Business Combination (a “Target”); provided, however,
that such indemnification of the Company by the Sponsor shall apply only to the extent necessary to ensure that such claims by a third
party for services rendered (other than the Company’s independent public accountants) or products sold to the Company or a Target
do not reduce the amount of funds in the Trust Account to below (i) $10.20 per share of the Offering Shares or (ii) such lesser amount
per share of the Offering Shares held in the Trust Account due to reductions in the value of the trust assets as of the date of the liquidation
of the Trust Account, in each case, net of the amount of interest earned on the property in the Trust Account which may be withdrawn
to pay taxes, except as to any claims by a third party (including a Target) who executed a waiver of any and all rights to seek access
to the Trust Account and except as to any claims under the Company’s indemnity of the Underwriters against certain liabilities,
including liabilities under the Securities Act. In the event that any such executed waiver is deemed to be unenforceable against such
third party, the Sponsor shall not be responsible to the extent of any liability for such third-party claims. The Sponsor shall have
the right to defend against any such claim with counsel of its choice reasonably satisfactory to the Company if, within 15 days following
written receipt of notice of the claim to the Sponsor, the Sponsor notifies the Company in writing that it shall undertake such defense.


 




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5. To
the extent that the Underwriters do not exercise their over-allotment option to purchase up to an additional 1,500,000 Units in full
within 45 days from the date of the Prospectus (and as further described in the Prospectus), the Sponsor agrees to forfeit, at no cost,
a number of Founder Shares in the aggregate equal to 375,000 multiplied by a fraction, (i) the numerator of which is 1,500,000 minus
the number of Units purchased by the Underwriters upon the exercise of their over-allotment option, and (ii) the denominator of which
is 1,500,000. The Sponsor will be required to forfeit only that number of Founder Shares as is necessary so that the Initial Stockholders
will own an aggregate of 20.0% of the Company’s issued and outstanding shares of Capital Stock after the Public Offering (excluding
the Representative’s shares as described in the Prospectus).


 


6. The
Sponsor and each Insider hereby agrees and acknowledges that: (i) the Underwriters and the Company would be irreparably injured in the
event of a breach by such Sponsor or an Insider of its, his or her obligations under paragraphs 1, 2, 3, 4, 5, 6, 7(a), 7(b), and 9 of
this Letter Agreement (ii) monetary damages may not be an adequate remedy for such breach and (iii) the non-breaching party shall be
entitled to injunctive relief, in addition to any other remedy that such party may have in law or in equity, in the event of such breach.


 


7.(a)The
Sponsor and each Insider agrees that it or he shall not Transfer any Founder Shares (or shares of Common Stock issuable upon conversion
thereof) until the earlier of (A) one year after the date of the Company’s initial Business Combination or (B) subsequent to the
Company’s initial Business Combination, (x) if the reported last sale price of the Common Stock equals or exceeds $12.00 per share
(as adjusted for stock splits, stock dividends, right issuances, reorganizations, recapitalizations and the like) for any 20 trading
days within any 30-trading day period commencing at least 150 days after the Company’s initial Business Combination, or (y) the
date on which the Company completes a liquidation, merger, capital stock exchange, reorganization or other similar transaction that results
in all of our stockholders having the right to exchange their shares of common stock for cash, securities or other property (the “Founder
Shares Lock-up Period”).


 


(b) The
Sponsor and each Insider agrees that it, he or she shall not Transfer any Private Placement Warrants or shares of Common Stock issued
or issuable upon the exercise of the Private Placement Warrants, until 30 days after the completion of the initial Business Combination
(the “Private Placement Lock-up Period”, together with the Founder Shares Lock-up Period, the “Lock-up Periods”).


 




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(c) Notwithstanding
the provisions set forth in paragraphs 7(a) and 7(b), Transfers of the Founder Shares, Private Placement Warrants and shares of Common
Stock issued or issuable upon the exercise or conversion of the Private Placement Warrants or the Founder Shares that are held by the
Sponsor, any Insider or any of their permitted transferees (that have complied with this paragraph 7(c)), are permitted (i) to the Company’s
officers or directors, any affiliate or family member of any of the Company’s officers or directors or any members of the Sponsor
or any affiliates of the Sponsor; (b) in the case of an individual, by gift to a member of such individual’s immediate family or
to a trust, the beneficiary of which is a member of such individual’s immediate family, an affiliate of such individual or to a
charitable organization; (c) in the case of an individual, by virtue of laws of descent and distribution upon death of such individual;
(d) in the case of an individual, pursuant to a qualified domestic relations order; (e) by private sales or transfers made in connection
with the consummation of an initial Business Combination at prices no greater than the price at which the securities were originally
purchased; (f) in the event of the Company’s liquidation prior to the completion of an initial Business Combination; (g) by virtue
of the laws of the State of Delaware or the Sponsor’s limited liability company agreement upon dissolution of the Sponsor; or (h)
in the event of the Company’s liquidation, merger, capital stock exchange, reorganization or other similar transaction which results
in all of the Company’s stockholders having the right to exchange their shares of Common Stock for cash, securities or other property
subsequent to the Company’s completion of an initial Business Combination; provided, however, that in the case of clauses (a) through
(e) or (g), these permitted transferees must enter into a written agreement with the Company agreeing to be bound by the transfer restrictions
herein and the other restrictions contained in this Agreement (including provisions relating to voting, the Trust Account and liquidating
distributions).


 


8. Each
of the Sponsor and the Insiders represents and warrants that it, he or she has never been suspended or expelled from membership in any
securities or commodities exchange or association or had a securities or commodities license or registration denied, suspended or revoked.
Each Insider’s biographical information furnished to the Company (including any such information included in the Prospectus) is
true and accurate in all respects and does not omit any material information with respect to the Insider’s background. The Sponsor
and each Insider’s questionnaire furnished to the Company is true and accurate in all respects. The Sponsor and each Insider represents
and warrants that: it, he or she is not subject to or a respondent in any legal action for, any injunction, cease-and-desist order or
order or stipulation to desist or refrain from any act or practice relating to the offering of securities in any jurisdiction; it, he
or she has never been convicted of, or pleaded guilty to, any crime (i) involving fraud, (ii) relating to any financial transaction or
handling of funds of another person, or (iii) pertaining to any dealings in any securities and it, he or she is not currently a defendant
in any such criminal proceeding. The Company represents and warrants that, to its knowledge, (i) none of its advisors has been suspended
or expelled from membership in any securities or commodities exchange or association or had a securities or commodities license or registration
denied, suspended or revoked, (ii) each advisor’s biographical information furnished to the Company (including any such information
included in the Prospectus) is true and accurate in all respects and does not omit any material information with respect to such advisor’s
background and each advisor’s questionnaire furnished to the Company is true and accurate in all respects, (iii) none of its advisors
is subject to or a respondent in any legal action for, any injunction, cease-and-desist order or order or stipulation to desist or refrain
from any act or practice relating to the offering of securities in any jurisdiction; and (iii) none of its advisors has been convicted
of, or pleaded guilty to, any crime (x) involving fraud, (y) relating to any financial transaction or handling of funds of another person,
or (z) pertaining to any dealings in any securities and none of its advisors is currently a defendant in any such criminal proceeding.


 




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9. Except
as disclosed in the Prospectus and cash or other compensation to the Company’s officers or advisors to be engaged subsequent to
the consummation of the Public Offering (which will be disclosed in the Company’s other filings with the Securities and Exchange
Commission), neither the Sponsor nor any individual who is an officer, director or advisor of the Company as of the date hereof nor any
affiliate thereof shall receive from the Company any finder’s fee, reimbursement, consulting fee, monies in respect of any repayment
of a loan or other compensation prior to, or in connection with any services rendered in order to effectuate the consummation of the
Company’s initial Business Combination (regardless of the type of transaction that it is), other than the following, none of which
will be made from the proceeds held in the Trust Account prior to the completion of the initial Business Combination: repayment of a
loan and advances up to an aggregate of $300,000 made to the Company by Aesther Healthcare Sponsor, LLC; reimbursement for any out-of-pocket
expenses related to identifying, investigating and consummating an initial Business Combination; payment to an affiliate of the Sponsor
of $10,000 per month, for up to 18 months, for office space, utilities and secretarial and administrative support; and repayment of non-interest
bearing loans, if any, and on such terms as to be determined by the Company from time to time, made by the Sponsor or any of the Company’s
officers or directors to finance transaction costs in connection with an intended initial Business Combination, provided, that, if the
Company does not consummate an initial Business Combination, a portion of the working capital held outside the Trust Account may be used
by the Company to repay such loaned amounts so long as no proceeds from the Trust Account are used for such repayment. Up to $1,500,000
of such loans may be convertible into warrants, at a price of $1.00 per warrant, at the option of the lender, upon consummation of the
initial Business Combination. The warrants would be identical to the Private Placement Warrants.


 


10. Each
of the Sponsor and each Insider has full right and power, without violating any agreement to which it is bound (including, without limitation,
any non-competition or non-solicitation agreement with any employer or former employer), to enter into this Letter Agreement and, as
applicable, to serve as an officer and/or a director on the board of directors of the Company and hereby consents to being named in the
Prospectus as an officer and/or a director of the Company.


 


11. As
used herein, (i) “Business Combination” shall mean a merger, capital stock exchange, asset acquisition, stock purchase,
reorganization or similar business combination, involving the Company and one or more businesses; (ii) “Capital Stock”
shall mean, collectively, the Common Stock and the Founder Shares; (iii) “Founder Shares” shall mean the 2,875,000
shares of the Company’s Class B common stock, par value $0.0001 per share, initially held by the Sponsor (up to 375,000 Shares
of which are subject to complete or partial forfeiture by the Sponsor if the over-allotment option is not exercised in full by the Underwriters);
(iv) “Initial Stockholders” shall mean the Sponsor and any other holder of Founder Shares immediately prior to the
Public Offering; (v) “Private Placement Warrants” shall mean the 5,261,000 warrants to purchase shares of Common Stock
comprising the Private Placement Warrants (or up to 5,711,000 warrants to purchase shares of Common Stock if the over-allotment option
is exercised in full); (vi) “Public Stockholders” shall mean the holders of securities issued in the Public Offering;
(vii) “Trust Account” shall mean the trust fund into which a portion of the net proceeds of the Public Offering and
the sale of the Private Placement Units shall be deposited; and (viii) “Transfer” shall mean the (a) sale or assignment
of, offer to sell, contract or agreement to sell, hypothecate, pledge, grant of any option to purchase or otherwise dispose of or agreement
to dispose of, directly or indirectly, or establishment or increase of a put equivalent position or liquidation with respect to or decrease
of a call equivalent position within the meaning of Section 16 of the Securities Exchange Act of 1934, as amended, and the rules and
regulations of the Commission promulgated thereunder with respect to, any security, (b) entry into any swap or other arrangement that
transfers to another, in whole or in part, any of the economic consequences of ownership of any security, whether any such transaction
is to be settled by delivery of such securities, in cash or otherwise, or (c) public announcement of any intention to effect any transaction
specified in clause (a) or (b).


 




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12. This
Letter Agreement constitutes the entire agreement and understanding of the parties hereto in respect of the subject matter hereof and
supersedes all prior understandings, agreements, or representations by or among the parties hereto, written or oral, to the extent they
relate in any way to the subject matter hereof or the transactions contemplated hereby. This Letter Agreement may not be changed, amended,
modified or waived (other than to correct a typographical error) as to any particular provision, except by a written instrument executed
by all parties hereto.


 


13. No
party hereto may assign either this Letter Agreement or any of its rights, interests, or obligations hereunder without the prior written
consent of the other parties. Any purported assignment in violation of this paragraph shall be void and ineffectual and shall not operate
to transfer or assign any interest or title to the purported assignee. This Letter Agreement shall be binding on the Sponsor and each
Insider and their respective successors, heirs and assigns and permitted transferees.


 


14. Nothing
in this Letter Agreement shall be construed to confer upon, or give to, any person or corporation other than the parties hereto any right,
remedy or claim under or by reason of this Letter Agreement or of any covenant, condition, stipulation, promise or agreement hereof.
All covenants, conditions, stipulations, promises and agreements contained in this Letter Agreement shall be for the sole and exclusive
benefit of the parties hereto and their successors, heirs, personal representatives and assigns and permitted transferees.


 


15. This
Letter Agreement may be executed in any number of original or facsimile counterparts and each of such counterparts shall for all purposes
be deemed to be an original, and all such counterparts shall together constitute but one and the same instrument.


 


16. This
Letter Agreement shall be deemed severable, and the invalidity or unenforceability of any term or provision hereof shall not affect the
validity or enforceability of this Letter Agreement or of any other term or provision hereof. Furthermore, in lieu of any such invalid
or unenforceable term or provision, the parties hereto intend that there shall be added as a part of this Letter Agreement a provision
as similar in terms to such invalid or unenforceable provision as may be possible and be valid and enforceable.


 


17. This
Letter Agreement shall be governed by and construed and enforced in accordance with the laws of the State of New York, without giving
effect to conflicts of law principles that would result in the application of the substantive laws of another jurisdiction. The parties
hereto (i) all agree that any action, proceeding, claim or dispute arising out of, or relating in any way to, this Letter Agreement shall
be brought and enforced in the courts of New York City, in the State of New York, and irrevocably submit to such jurisdiction and venue,
which jurisdiction and venue shall be exclusive and (ii) waive any objection to such exclusive jurisdiction and venue or that such courts
represent an inconvenient forum.


 


18. Any
notice, consent or request to be given in connection with any of the terms or provisions of this Letter Agreement shall be in writing
and shall be sent by express mail or similar private courier service, by certified mail (return receipt requested), by hand delivery
or facsimile transmission.


 


19. This
Letter Agreement shall terminate on the earlier of (i) the expiration of the Lock-up Periods or (ii) the liquidation of the Company;
provided, however, that this Letter Agreement shall earlier terminate in the event that the Public Offering is not consummated and closed
by September 30, 2021; provided further that paragraph 4 of this Letter Agreement shall survive such liquidation.


 




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	 	Sincerely,
	 	 
	 	Aesther
    Healthcare Acquisition Corp.
	 	 
	 	By:	/s/
    Suren Ajjarapu
	 	Name:	Suren
    Ajjarapu
	 	Title:	Chief
    Executive Officer
	 	 	 
	 	 	/s/ Suren
    Ajjarapu
	 	Name:	Suren
    Ajjarapu
	 	 	 
	 	 	/s/
    Howard Doss
	 	Name:	Howard
    Doss
	 	 	 
	 	 	/s/
    Michael L. Peterson
	 	Name:	Michael
    L. Peterson
	 	 	 
	 	 	/s/
    Venkatesh Srinivasan
	 	Name:	Venkatesh
    Srinivasan
	 	 	 
	 	 	/s/ Donald
    G. Fell
	 	Name:	Donald
    G. Fell
	 	 	 
	 	 	/s/ Siva
    Saravanan
	 	Name:	Siva
    Saravanan
	 	 	 
	 	Aesther Healthcare Sponsor, LLC
	 	 	 
	 	By:	/s/ Suren
    Ajjarapu
	 	By:	Suren
Ajjarapu, Chief Executive Officer


 


[Signature
Page to Letter Agreement]


 




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