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Exhibit 10.2

REGISTRATION RIGHTS AGREEMENT

        This Registration Rights Agreement (this "Agreement") is made and
entered into as of July 1, 2003, by and among AVANT Immunotherapeutics, Inc., a
Delaware corporation (the "Company"), and the investors signatory hereto (each a
"Purchaser" and collectively, the "Purchasers").

        This Agreement is made pursuant to the Securities Purchase Agreement,
dated as of the date hereof among the Company and the Purchasers (the "Purchase
Agreement").

        The Company and the Purchasers hereby agree as follows:

        1.    Definitions.    Capitalized terms used and not otherwise defined
herein that are defined in the Purchase Agreement shall have the meanings given
such terms in the Purchase Agreement. As used in this Agreement, the following
terms shall have the following meanings:

        "Advice" shall have the meaning set forth in Section 6(d).

        "Effectiveness Date" means, with respect to the Registration Statement
required to be filed hereunder, the earlier of (a) the 45th calendar day
following the Closing Date (75th calendar day in the event of a full review by
the Commission) and (b) the fifth Trading Day following the date on which the
Company is notified by the Commission that the Registration Statement will not
be reviewed or is no longer subject to further review and comments.

        "Effectiveness Period" shall have the meaning set forth in Section 2(a).

        "Event" shall have the meaning set forth in Section 2(b).

        "Event Date" shall have the meaning set forth in Section 2(b).

        "Filing Date" means, with respect to the Registration Statement required
to be filed hereunder, the 7th Trading Day following the Closing Date.

        "Holder" or "Holders" means the holder or holders, as the case may be,
from time to time of Registrable Securities.

        "Indemnified Party" shall have the meaning set forth in Section 5(c).

        "Indemnifying Party" shall have the meaning set forth in Section 5(c).

        "Losses" shall have the meaning set forth in Section 5(a).

        "Proceeding" means an action, claim, suit, investigation or proceeding
(including, without limitation, an investigation or partial proceeding, such as
a deposition), whether commenced or threatened.

        "Prospectus" means the prospectus included in the Registration Statement
(including, without limitation, a prospectus that includes any information
previously omitted from a prospectus filed as part of an effective registration
statement in reliance upon Rule 430A promulgated under the Securities Act), as
amended or supplemented by any prospectus supplement, with respect to the terms
of the offering of any portion of the Registrable Securities covered by the
Registration Statement, and all other amendments and supplements to the
Prospectus, including post-effective amendments, and all material incorporated
by reference or deemed to be incorporated by reference in such Prospectus.

        "Registrable Securities" means the Shares and the Warrant Shares,
together with any shares of Common Stock issued or issuable upon any stock
split, dividend or other distribution, recapitalization or similar event with
respect to the foregoing, but excluding Shares or Warrant Shares (a) for which a
Registration Statement shall have become effective under the Securities Act and
which have been disposed of under such Registration Statement, (b) which have
been sold

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pursuant to an exemption from the registration requirements of the Securities
Act, (c) which are eligible to be sold pursuant to Rule 144 (or any successor
provision) so long as the volume limitations thereunder, if applicable, would
not prevent the sale by the Holder thereof of all such Holder's Shares and
Warrant Shares within a single three-month period and (d) which are eligible for
sale pursuant to Rule 144(k) (or any successor provision).

        "Registration Statement" means the registration statements required to
be filed hereunder, including (in each case) the Prospectus, amendments and
supplements to the registration statement or Prospectus, including pre- and
post-effective amendments, all exhibits thereto, and all material incorporated
by reference or deemed to be incorporated by reference in the registration
statement.

        "Rule 144" means Rule 144 promulgated by the Commission pursuant to the
Securities Act, as such Rule may be amended from time to time, or any similar
rule or regulation hereafter adopted by the Commission having substantially the
same effect as such Rule.

        "Rule 415" means Rule 415 promulgated by the Commission pursuant to the
Securities Act, as such Rule may be amended from time to time, or any similar
rule or regulation hereafter adopted by the Commission having substantially the
same effect as such Rule.

        "Rule 424" means Rule 424 promulgated by the Commission pursuant to the
Securities Act, as such Rule may be amended from time to time, or any similar
rule or regulation hereafter adopted by the Commission having substantially the
same effect as such Rule.

        "Securities Act" means the Securities Act of 1933, as amended.

        2.    Registration.    

        (a)   On or prior to the Filing Date, the Company shall prepare and file
with the Commission the Registration Statement covering the resale of all of the
Registrable Securities for an offering to be made on a continuous basis pursuant
to Rule 415. The Registration Statement required hereunder shall be on Form S-3
(except if the Company is not then eligible to register for resale the
Registrable Securities on Form S-3, in which case the Registration shall be on
another appropriate form in accordance herewith). The Registration Statement
required hereunder shall contain (except if otherwise directed by the Holders)
the "Plan of Distribution" attached hereto as Annex A. The Company shall cause
the Registration Statement to become effective and remain effective as provided
herein. The Company shall use its commercially reasonable efforts to cause the
Registration Statement to be declared effective under the Securities Act as
promptly as possible after the filing thereof, but in any event not later than
the Effectiveness Date, and shall use its commercially reasonable efforts to
keep the Registration Statement continuously effective under the Securities Act
until the date which is two (2) years after the Closing Date or such later date
when all Shares and Warrant Shares cease to be "Registrable Securities" (the
"Effectiveness Period").

        (b)   If: (i) a Registration Statement is not filed on or prior to its
Filing Date (if the Company files a Registration Statement without affording the
Holder the opportunity to review and comment on the same as required by
Section 3(a), the Company shall not be deemed to have satisfied this
clause (i)); provided, however, that if a Holder fails to provide the Company
with any information that is required to be provided in the Registration
Statement with respect to such Holder pursuant to Section 3(k), then the Filing
Date shall be extended until two (2) Trading Days following the date of receipt
by the Company of such required information, or (ii) the Company fails to file
with the Commission a request for acceleration in accordance with Rule 461
promulgated under the Securities Act, within five (5) Trading Days of the date
that the Company is notified (orally or in writing, whichever is earlier) by the
Commission that a Registration Statement will not be "reviewed," or not subject
to further review, or (iii) prior to the date when such Registration Statement
is first declared effective by the Commission, the Company fails to

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file a pre-effective amendment and otherwise respond in writing to comments made
by the Commission in respect of such Registration Statement within fifteen
(15) Trading Days after the receipt of comments by or notice from the Commission
that such amendment is required in order for a Registration Statement to be
declared effective, or (iv) a Registration Statement filed or required to be
filed hereunder is not declared effective by the Commission on or before the
Effectiveness Date, or (v) after a Registration Statement is first declared
effective by the Commission, it ceases for any reason to remain continuously
effective as to all Registrable Securities for which it is required to be
effective, or the Holders are not permitted to utilize the Prospectus therein to
resell such Registrable Securities, for in any such cases twenty (20) Trading
Days (which need not be consecutive days) in the aggregate during any 12-month
period (any such failure or breach being referred to as an "Event," and for
purposes of clause (i) or (iv) the date on which such Event occurs, or for
purposes of clause (ii) the date on which such five (5) Trading Day period is
exceeded, or for purposes of clauses (iii) the date which such fifteen
(15) Trading Day period is exceeded, or for purposes of clause (v) the date on
which such twenty (20) Trading Day period is exceeded being referred to as
"Event Date"), then in addition to any other rights the Holders may have
hereunder or under applicable law: (x) on each such Event Date the Company shall
pay to each Holder an amount in cash, as liquidated damages and not as a
penalty, equal to 2% of the aggregate purchase price paid by such Holder
pursuant to the Purchase Agreement for any Registrable Securities then held by
such Holder (pro-rated for partial periods on a per diem basis); and (y) on each
monthly anniversary of each such Event Date (if the applicable Event shall not
have been cured by such date) until the applicable Event is cured, the Company
shall pay to each Holder an amount in cash, as liquidated damages and not as a
penalty, equal to 2% of the aggregate purchase price paid by such Holder
pursuant to the Purchase Agreement for any Registrable Securities then held by
such Holder (pro-rated for partial periods on a per diem basis). If the Company
fails to pay any liquidated damages pursuant to this Section in full within
seven (7) days after the date payable, the Company will pay interest thereon at
a rate of 18% per annum (or such lesser maximum amount that is permitted to be
paid by applicable law) to the Holder, accruing daily from the date such
liquidated damages are payable until such amounts, plus all such interest
thereon, are paid in full.

        (c)   If during the Effectiveness Period, the number of Registrable
Securities at any time exceeds 100% of the number of shares of Common Stock then
registered in a Registration Statement, then the Company shall file as soon as
reasonably practicable but in any case prior to the 30th day following the date
such number is exceeded, an additional Registration Statement covering the
resale of by the Holders of not less than all of such Registrable Securities and
the Company shall use commercially reasonable efforts to cause such Registration
Statement to be declared effective as soon as reasonably practible thereafter.

        3.    Registration Procedures    

        In connection with the Company's registration obligations hereunder, the
Company shall:

        (a)   Not less than three (3) Trading Days prior to the filing of the
Registration Statement or any related Prospectus or any amendment or supplement
thereto, (i) furnish to the Holders copies of all such documents proposed to be
filed (including documents incorporated or deemed incorporated by reference to
the extent requested by such Person) which documents will be subject to the
review of such Holders, and (ii) cause its officers and directors, counsel and
independent certified public accountants to respond to such inquiries as shall
be necessary, in the reasonable opinion of respective counsel to conduct a
reasonable investigation within the meaning of the Securities Act.

        (b)   (i) Prepare and file with the Commission such amendments,
including post-effective amendments, to the Registration Statement and the
Prospectus used in connection therewith as

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may be necessary to keep the Registration Statement continuously effective as to
the applicable Registrable Securities for the Effectiveness Period and prepare
and file with the Commission such additional Registration Statements in order to
register for resale under the Securities Act all of the Registrable Securities;
(ii) cause the related Prospectus to be amended or supplemented by any required
Prospectus supplement, and as so supplemented or amended to be filed pursuant to
Rule 424; (iii) respond as promptly as reasonably possible, and in any event
within ten (10) Trading Days, to any comments received from the Commission with
respect to the Registration Statement or any amendment thereto and, as promptly
as reasonably possible, upon request, provide the Holders true and complete
copies of all correspondence from and to the Commission relating to the
Registration Statement; and (iv) comply in all material respects with the
provisions of the Securities Act and the Exchange Act with respect to the
disposition of all Registrable Securities covered by the Registration Statement
during the applicable period in accordance with the intended methods of
disposition by the Holders thereof set forth in the Registration Statement as so
amended or in such Prospectus as so supplemented.

        (c)   Notify the Holders of Registrable Securities to be sold as
promptly as reasonably possible (and, in the case of (i)(A) below, not less than
two (2) Trading Days prior to such filing) and (if requested by any such Person)
confirm such notice in writing promptly following the day (i)(A) when a
Prospectus or any Prospectus supplement or post-effective amendment to the
Registration Statement is proposed to be filed; (B) when the Commission notifies
the Company whether there will be a "review" of the Registration Statement and
whenever the Commission comments in writing on the Registration Statement (the
Company shall upon request provide true and complete copies thereof and all
written responses thereto to each of the Holders); and (C) with respect to the
Registration Statement or any post-effective amendment, when the same has become
effective; (ii) of any request by the Commission or any other Federal or state
governmental authority during the Effectiveness Period of the Registration
Statement for amendments or supplements to the Registration Statement or
Prospectus or for additional information; (iii) of the issuance by the
Commission or any other federal or state governmental authority of any stop
order suspending the effectiveness of the Registration Statement covering any or
all of the Registrable Securities or the initiation of any Proceedings for that
purpose; (iv) of the receipt by the Company of any notification with respect to
the suspension of the qualification or exemption from qualification of any of
the Registrable Securities for sale in any jurisdiction, or the initiation or
threatening of any Proceeding for such purpose; and (v) of the occurrence of any
event or passage of time that makes the financial statements included in the
Registration Statement ineligible for inclusion therein or any statement made in
the Registration Statement or Prospectus or any document incorporated or deemed
to be incorporated therein by reference untrue in any material respect or that
requires any revisions to the Registration Statement, Prospectus or other
documents so that, in the case of the Registration Statement or the Prospectus,
as the case may be, it will not contain any untrue statement of a material fact
or omit to state any material fact required to be stated therein or necessary to
make the statements therein, in light of the circumstances under which they were
made, not misleading.

        (d)   Use its commercially reasonable efforts to avoid the issuance of,
or, if issued, obtain the withdrawal of (i) any order suspending the
effectiveness of the Registration Statement, or (ii) any suspension of the
qualification (or exemption from qualification) of any of the Registrable
Securities for sale in any jurisdiction, at the earliest practicable moment.

        (e)   Furnish to each Holder, without charge, at least one (1) conformed
copy of the Registration Statement and each amendment thereto, including
financial statements and schedules, all documents incorporated or deemed to be
incorporated therein by reference to the extent requested by such Person, and
all exhibits to the extent requested by such Person (including those

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previously furnished or incorporated by reference) promptly after the filing of
such documents with the Commission.

        (f)    Promptly deliver to each Holder, without charge, as many copies
of the Prospectus or Prospectuses (including each form of prospectus) and each
amendment or supplement thereto as such Persons may reasonably request in
connection with resales by the Holder of Registrable Securities. The Company
hereby consents to the use of such Prospectus and each amendment or supplement
thereto by each of the selling Holders in connection with the offering and sale
of the Registrable Securities covered by such Prospectus and any amendment or
supplement thereto, except after the giving on any notice pursuant to
Section 3(c).

        (g)   Prior to any resale of Registrable Securities by a Holder, use its
commercially reasonable efforts to register or qualify or cooperate with the
selling Holders in connection with the registration or qualification (or
exemption from the Registration or qualification) of such Registrable Securities
for the resale by the Holder under the securities or Blue Sky laws of such
jurisdictions within the United States as any Holder reasonably requests in
writing, to keep each the Registration or qualification (or exemption therefrom)
effective during the Effectiveness Period and to do any and all other acts or
things reasonably necessary to enable the disposition in such jurisdictions of
the Registrable Securities covered by the Registration Statement; provided, that
the Company shall not be required to qualify generally to do business in any
jurisdiction where it is not then so qualified, subject the Company to any
material tax in any such jurisdiction where it is not then so subject or file a
general consent to service of process in any such jurisdiction.

        (h)   If requested by the Holders, cooperate with the Holders to
facilitate the timely preparation and delivery of certificates representing
Registrable Securities to be delivered to a transferee pursuant to the
Registration Statement, which certificates shall be free, to the extent
permitted by the Purchase Agreement, of all restrictive legends, and to enable
such Registrable Securities to be in such denominations and registered in such
names as any such Holders may request.

        (i)    Upon the occurrence of any event contemplated by Section 3(c)(v),
as promptly as reasonably possible, prepare a supplement or amendment, including
a post-effective amendment, to the Registration Statement or a supplement to the
related Prospectus or any document incorporated or deemed to be incorporated
therein by reference, and file any other required document so that, as
thereafter delivered, neither the Registration Statement nor such Prospectus
will contain an untrue statement of a material fact or omit to state a material
fact required to be stated therein or necessary to make the statements therein,
in light of the circumstances under which they were made, not misleading.

        (j)    Comply with all applicable rules and regulations of the
Commission.

        (k)   The Company may require each selling Holder to furnish to the
Company a certified statement as to the number of shares of Common Stock
beneficially owned by such Holder and, if required by the Commission, the person
thereof that has voting and dispositive control over the Shares.

        4.    Registration Expenses.    All fees and expenses incident to the
performance of or compliance with this Agreement by the Company shall be borne
by the Company whether or not any Registrable Securities are sold pursuant to
the Registration Statement. The fees and expenses referred to in the foregoing
sentence shall include, without limitation, (a) all registration and filing fees
(including, without limitation, fees and expenses (i) with respect to filings
required to be made with the Trading Market on which the Common Stock is then
listed for trading, and (ii) in compliance with applicable state securities or
Blue Sky laws), (b) printing expenses (including, without limitation, expenses
of printing certificates for Registrable Securities and of printing prospectuses
if the printing of

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prospectuses is reasonably requested by the holders of a majority of the
Registrable Securities included in the Registration Statement), (c) messenger,
telephone and delivery expenses, (d) fees and disbursements of counsel for the
Company, (e) Securities Act liability insurance, if the Company so desires such
insurance, and (f) fees and expenses of all other Persons retained by the
Company in connection with the consummation of the transactions contemplated by
this Agreement. In addition, the Company shall be responsible for all of its
internal expenses incurred in connection with the consummation of the
transactions contemplated by this Agreement (including, without limitation, all
salaries and expenses of its officers and employees performing legal or
accounting duties), the expense of any annual audit and the fees and expenses
incurred in connection with the listing of the Registrable Securities on any
securities exchange as required hereunder.

        5.    Indemnification    

        (a)    Indemnification by the Company.    The Company shall,
notwithstanding any termination of this Agreement, indemnify and hold harmless
each Holder, the officers, directors, agents and employees of each of them, each
Person who controls any such Holder (within the meaning of Section 15 of the
Securities Act or Section 20 of the Exchange Act) and the officers, directors,
agents and employees of each such controlling Person, to the fullest extent
permitted by applicable law, from and against any and all losses, claims,
damages, liabilities, costs (including, without limitation, reasonable
attorneys' fees) and expenses (collectively, "Losses"), as incurred, to the
extent arising out of or relating to any untrue or alleged untrue statement of a
material fact contained in the Registration Statement, any Prospectus or any
form of prospectus or in any amendment or supplement thereto or in any
preliminary prospectus, or arising out of or relating to any omission or alleged
omission of a material fact required to be stated therein or necessary to make
the statements therein (in the case of any Prospectus or form of prospectus or
supplement thereto, in light of the circumstances under which they were made)
not misleading, except to the extent, but only to the extent, that (i) such
untrue statements or omissions are based solely upon information regarding such
Holder furnished in writing to the Company by such Holder expressly for use
therein, or to the extent that such information relates to such Holder or such
Holder's proposed method of distribution of Registrable Securities and was
reviewed and expressly approved in writing by such Holder expressly for use in
the Registration Statement, such Prospectus or such form of Prospectus or in any
amendment or supplement thereto (it being understood that the Holder has
approved Annex A hereto for this purpose) or (ii) in the case of an occurrence
of an event of the type specified in Section 3(c)(ii)-(v), the use by such
Holder of an outdated or defective Prospectus after the Company has notified
such Holder in writing that the Prospectus is outdated or defective and prior to
the receipt by such Holder of the Advice contemplated in Section 6(d). The
Company shall notify the Holders promptly of the institution, threat or
assertion of any Proceeding of which the Company is aware in connection with the
transactions contemplated by this Agreement.

        (b)    Indemnification by Holders.    Each Holder shall, severally and
not jointly, indemnify and hold harmless the Company, its directors, officers,
agents and employees, each Person who controls the Company (within the meaning
of Section 15 of the Securities Act and Section 20 of the Exchange Act), and the
directors, officers, agents or employees of such controlling Persons, to the
fullest extent permitted by applicable law, from and against all Losses, as
incurred, to the extent arising out of or based upon: (i) such Holder's failure
to comply with the prospectus delivery requirements of the Securities Act or
(ii) any untrue or alleged untrue statement of a material fact contained in any
Registration Statement, any Prospectus, or any form of prospectus, or in any
amendment or supplement thereto or in any preliminary prospectus, or arising out
of or relating to any omission or alleged omission of a material fact required
to be stated therein or necessary to make the statements therein not misleading
(A) to the extent, but only to the extent, that such untrue statement or
omission is contained in any information so furnished in writing by such

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Holder to the Company specifically for inclusion in the Registration Statement
or such Prospectus or (B) to the extent that (1) such untrue statements or
omissions are based solely upon information regarding such Holder furnished in
writing to the Company by such Holder expressly for use therein, or to the
extent that such information relates to such Holder or such Holder's proposed
method of distribution of Registrable Securities and was reviewed and expressly
approved in writing by such Holder expressly for use in the Registration
Statement (it being understood that the Holder has approved Annex A hereto for
this purpose), such Prospectus or such form of Prospectus or in any amendment or
supplement thereto or (2) in the case of an occurrence of an event of the type
specified in Section 3(c)(ii)-(v), the use by such Holder of an outdated or
defective Prospectus after the Company has notified such Holder in writing that
the Prospectus is outdated or defective and prior to the receipt by such Holder
of the Advice contemplated in Section 6(d). In no event shall the liability of
any selling Holder hereunder be greater in amount than the dollar amount of the
net proceeds received by such Holder upon the sale of the Registrable Securities
giving rise to such indemnification obligation.

        (c)    Conduct of Indemnification Proceedings.    If any Proceeding
shall be brought or asserted against any Person entitled to indemnity hereunder
(an "Indemnified Party"), such Indemnified Party shall promptly notify the
Person from whom indemnity is sought (the "Indemnifying Party") in writing, and
the Indemnifying Party shall have the right to assume the defense thereof,
including the employment of counsel reasonably satisfactory to the Indemnified
Party and the payment of all fees and expenses incurred in connection with
defense thereof; provided, that the failure of any Indemnified Party to give
such notice shall not relieve the Indemnifying Party of its obligations or
liabilities pursuant to this Agreement, except (and only) to the extent that it
shall be finally determined by a court of competent jurisdiction (which
determination is not subject to appeal or further review) that such failure
shall have prejudiced the Indemnifying Party.

        An Indemnified Party shall have the right to employ separate counsel in
any such Proceeding and to participate in the defense thereof, but the fees and
expenses of such counsel shall be at the expense of such Indemnified Party or
Parties unless: (i) the Indemnifying Party has agreed in writing to pay such
fees and expenses; (ii) the Indemnifying Party shall have failed promptly to
assume the defense of such Proceeding and to employ counsel reasonably
satisfactory to such Indemnified Party in any such Proceeding; or (iii) the
named parties to any such Proceeding (including any impleaded parties) include
both such Indemnified Party and the Indemnifying Party, and such Indemnified
Party shall have been advised by counsel that a conflict of interest is likely
to exist if the same counsel were to represent such Indemnified Party and the
Indemnifying Party (in which case, if such Indemnified Party notifies the
Indemnifying Party in writing that it elects to employ separate counsel at the
expense of the Indemnifying Party, the Indemnifying Party shall not have the
right to assume the defense thereof and the reasonable fees and expenses of one
separate counsel shall be at the expense of the Indemnifying Party). The
Indemnifying Party shall not be liable for any settlement of any such Proceeding
effected without its written consent, which consent shall not be unreasonably
withheld. No Indemnifying Party shall, without the prior written consent of the
Indemnified Party, effect any settlement of any pending Proceeding in respect of
which any Indemnified Party is a party, unless such settlement includes an
unconditional release of such Indemnified Party from all liability on claims
that are the subject matter of such Proceeding.

        All reasonable fees and expenses of the Indemnified Party (including
reasonable fees and expenses to the extent incurred in connection with
investigating or preparing to defend such Proceeding in a manner not
inconsistent with this Section) shall be paid to the Indemnified Party, as
incurred, within ten (10) Trading Days of written notice thereof to the
Indemnifying Party; provided, that the Indemnified Party shall promptly
reimburse the Indemnifying Party for that portion of such fees and expenses
applicable to such actions for which such Indemnified Party is not entitled to
indemnification hereunder, determined based upon the relative faults of the
parties.

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        (d)    Contribution.    If a claim for indemnification under
Section 5(a) or 5(b) is unavailable to an Indemnified Party (by reason of public
policy or otherwise), then each Indemnifying Party, in lieu of indemnifying such
Indemnified Party, shall contribute to the amount paid or payable by such
Indemnified Party as a result of such Losses, in such proportion as is
appropriate to reflect the relative fault of the Indemnifying Party and
Indemnified Party in connection with the actions, statements or omissions that
resulted in such Losses as well as any other relevant equitable considerations.
The relative fault of such Indemnifying Party and Indemnified Party shall be
determined by reference to, among other things, whether any action in question,
including any untrue or alleged untrue statement of a material fact or omission
or alleged omission of a material fact, has been taken or made by, or relates to
information supplied by, such Indemnifying Party or Indemnified Party, and the
parties' relative intent, knowledge, access to information and opportunity to
correct or prevent such action, statement or omission. The amount paid or
payable by a party as a result of any Losses shall be deemed to include, subject
to the limitations set forth in Section 5(c), any reasonable attorneys' or other
reasonable fees or expenses incurred by such party in connection with any
Proceeding to the extent such party would have been indemnified for such fees or
expenses if the indemnification provided for in this Section was available to
such party in accordance with its terms.

        The parties hereto agree that it would not be just and equitable if
contribution pursuant to this Section 5(d) were determined by pro rata
allocation or by any other method of allocation that does not take into account
the equitable considerations referred to in the immediately preceding paragraph.
Notwithstanding the provisions of this Section 5(d), no Holder shall be required
to contribute, in the aggregate, any amount in excess of the amount by which the
proceeds actually received by such Holder from the sale of the Registrable
Securities subject to the Proceeding exceeds the amount of any damages that such
Holder has otherwise been required to pay by reason of such untrue or alleged
untrue statement or omission or alleged omission, except in the case of fraud by
such Holder. The indemnity and contribution agreements contained in this Section
are in addition to any liability that the Indemnifying Parties may have to the
Indemnified Parties.

        6.    Miscellaneous    

        (a)    Remedies.    In the event of a breach by the Company or by a
Holder, of any of their obligations under this Agreement, each Holder or the
Company, as the case may be, in addition to being entitled to exercise all
rights granted by law and under this Agreement, including recovery of damages,
will be entitled to specific performance of its rights under this Agreement. The
Company and each Holder agree that monetary damages would not provide adequate
compensation for any losses incurred by reason of a breach by it of any of the
provisions of this Agreement and hereby further agrees that, in the event of any
action for specific performance in respect of such breach, it shall waive the
defense that a remedy at law would be adequate.

        (b)    No Piggyback on Registrations.    Neither the Company nor any of
its security holders (other than the Holders in such capacity pursuant hereto)
may include securities of the Company in a Registration Statement other than the
Registrable Securities, and the Company shall not after the date hereof enter
into any agreement providing any such right to any of its security holders.
Except as set forth in the SEC Reports, no Person has any right to cause the
Company to effect the registration under the Securities Act of any securities of
the Company. The Company shall not file any other registration statement until
after ten (10) Trading Days after the Effective Date.

        (c)    Compliance.    Each Holder covenants and agrees that it will
comply with the prospectus delivery requirements of the Securities Act as
applicable to it in connection with sales of Registrable Securities pursuant to
the Registration Statement.

        (d)    Discontinued Disposition.    Each Holder agrees by its
acquisition of such Registrable Securities that, upon receipt of a notice from
the Company of the occurrence of any event of the

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kind described in Section 3(c), such Holder will forthwith discontinue
disposition of such Registrable Securities under the Registration Statement
until such Holder's receipt of the copies of the supplemented Prospectus and/or
amended Registration Statement or until it is advised in writing (the "Advice")
by the Company that the use of the applicable Prospectus may be resumed, and, in
either case, has received copies of any additional or supplemental filings that
are incorporated or deemed to be incorporated by reference in such Prospectus or
Registration Statement. The Company may provide appropriate stop orders to
enforce the provisions of this paragraph.

        (e)    Piggy-Back Registrations.    If at any time during the
Effectiveness Period there is not an effective Registration Statement covering
all of the Registrable Securities and the Company shall determine to prepare and
file with the Commission a registration statement relating to an offering for
its own account or the account of others under the Securities Act of any of its
equity securities, other than on Form S-4 or Form S-8 (each as promulgated under
the Securities Act) or their then equivalents relating to equity securities to
be issued solely in connection with any acquisition of any entity or business or
equity securities issuable in connection with the stock option or other employee
benefit plans, then the Company shall send to each Holder a written notice of
such determination and, if within fifteen (15) days after the date of such
notice, any such Holder shall so request in writing, the Company shall include
in such registration statement all or any part of such Registrable Securities
such Holder requests to be registered, subject to customary underwriter cutbacks
applicable to all holders of registration rights.

        (f)    Amendments and Waivers.    The provisions of this Agreement,
including the provisions of this sentence, may not be amended, modified or
supplemented, and waivers or consents to departures from the provisions hereof
may not be given, unless the same shall be in writing and signed by the Company
and each Holder of the then outstanding Registrable Securities.

        (g)    Notices.    Any and all notices or other communications or
deliveries required or permitted to be provided hereunder shall be in writing
and shall be deemed given and effective on the earliest of (i) the date of
transmission, if such notice or communication is delivered via facsimile at the
facsimile number provided for below prior to 6:30 p.m. (New York City time) on a
Trading Day, (ii) the Trading Day after the date of transmission, if such notice
or communication is delivered via facsimile at the facsimile number provided for
below later than 6:30 p.m. (New York City time) on any date and earlier than
11:59 p.m. (New York City time) on such date, (iii) the Trading Day following
the date of mailing, if sent by nationally recognized overnight courier service,
or (iv) upon actual receipt by the party to whom such notice is required to be
given. The address for such notices and communications shall be delivered and
addressed as set forth in the Purchase Agreement.

        (h)    Successors and Assigns.    This Agreement shall inure to the
benefit of and be binding upon the successors and permitted assigns of each of
the parties and shall inure to the benefit of each Holder. Each Holder may
assign their respective rights hereunder in the manner and to the Persons as
permitted under the Purchase Agreement.

        (i)    Execution and Counterparts.    This Agreement may be executed in
any number of counterparts, each of which when so executed shall be deemed to be
an original and, all of which taken together shall constitute one and the same
Agreement. In the event that any signature is delivered by facsimile
transmission, such signature shall create a valid binding obligation of the
party executing (or on whose behalf such signature is executed) the same with
the same force and effect as if such facsimile signature were the original
thereof.

        (j)    Governing Law.    All questions concerning the construction,
validity, enforcement and interpretation of this Agreement shall be governed by
and construed and enforced in accordance with the internal laws of the State of
New York, without regard to the principles of conflicts of law

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thereof. Each party agrees that all legal proceedings concerning the
interpretations, enforcement and defense of the transactions contemplated by
this Agreement (whether brought against a party hereto or its respective
affiliates, directors, officers, shareholders, employees or agents) shall be
commenced exclusively in the state and federal courts sitting in the City of New
York, New York. Each party hereto hereby irrevocably submits to the exclusive
jurisdiction of the state and federal courts sitting in the City of New York,
New York for the adjudication of any dispute hereunder or in connection herewith
or with any transaction contemplated hereby or discussed herein (including with
respect to the enforcement of the any of this Agreement), and hereby irrevocably
waives, and agrees not to assert in any suit, action or proceeding, any claim
that it is not personally subject to the jurisdiction of any such court, that
such suit, action or proceeding is improper. Each party hereto hereby
irrevocably waives personal service of process and consents to process being
served in any such suit, action or proceeding by delivering a copy thereof via
overnight delivery (with evidence of delivery) to such party at the address in
effect for notices to it under this Agreement and agrees that such service shall
constitute good and sufficient service of process and notice thereof. Nothing
contained herein shall be deemed to limit in any way any right to serve process
in any manner permitted by law. Each party hereto hereby irrevocably waives, to
the fullest extent permitted by applicable law, any and all right to trial by
jury in any legal proceeding arising out of or relating to this Agreement or the
transactions contemplated hereby. If either party shall commence an action or
proceeding to enforce any provisions of this Agreement, then the prevailing
party in such action or proceeding shall be reimbursed by the other party for
its attorneys' fees and other costs and expenses incurred with the
investigation, preparation and prosecution of such action or proceeding.

        (k)    Cumulative Remedies.    The remedies provided herein are
cumulative and not exclusive of any remedies provided by law.

        (l)    Severability.    If any term, provision, covenant or restriction
of this Agreement is held by a court of competent jurisdiction to be invalid,
illegal, void or unenforceable, the remainder of the terms, provisions,
covenants and restrictions set forth herein shall remain in full force and
effect and shall in no way be affected, impaired or invalidated, and the parties
hereto shall use their commercially reasonable efforts to find and employ an
alternative means to achieve the same or substantially the same result as that
contemplated by such term, provision, covenant or restriction. It is hereby
stipulated and declared to be the intention of the parties that they would have
executed the remaining terms, provisions, covenants and restrictions without
including any of such that may be hereafter declared invalid, illegal, void or
unenforceable.

        (m)    Headings.    The headings in this Agreement are for convenience
of reference only and shall not limit or otherwise affect the meaning hereof.

        (n)    Independent Nature of Purchasers' Obligations and Rights.    The
obligations of each Purchaser hereunder is several and not joint with the
obligations of any other Purchaser hereunder, and no Purchaser shall be
responsible in any way for the performance of the obligations of any other
Purchaser hereunder. Nothing contained herein or in any other agreement or
document delivered at any closing, and no action taken by any Purchaser pursuant
hereto or thereto, shall be deemed to constitute the Purchasers as a
partnership, an association, a joint venture or any other kind of entity, or
create a presumption that the Purchasers are in any way acting in concert with
respect to such obligations or the transactions contemplated by this Agreement.
Each Purchaser shall be entitled to protect and enforce its rights, including
without limitation the rights arising out of this Agreement, and it shall not be
necessary for any other Purchaser to be joined as an additional party in any
proceeding for such purpose.

*************************

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        IN WITNESS WHEREOF, the parties have executed this Registration Rights
Agreement as of the date first written above.

    AVANT IMMUNOTHERAPEUTICS, INC.
 
 
By:
/s/  UNA S. RYAN      

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Name:  Una S. Ryan, Ph.D
Title:    President and Chief Executive Officer

[PURCHASERS' SIGNATURE PAGES TO FOLLOW]

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[PURCHASER'S RRA SIGNATURE PAGE]

    THE RIVERVIEW GROUP, LLC
 
 
By:
/s/  TERRY FEENEY      

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Name:  Terry Feeney
Title:    Chief Operating Officer

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ANNEX A

Plan of Distribution

        The Selling Stockholders and any of their pledgees, assignees and
successors-in-interest may, from time to time, sell any or all of their shares
of Common Stock on any stock exchange, market or trading facility on which the
shares are traded or in private transactions. These sales may be at fixed or
negotiated prices. The Selling Stockholders may use any one or more of the
following methods when selling shares:

•ordinary brokerage transactions and transactions in which the broker-dealer
solicits purchasers;

•block trades in which the broker-dealer will attempt to sell the shares as
agent but may position and resell a portion of the block as principal to
facilitate the transaction;

•purchases by a broker-dealer as principal and resale by the broker-dealer for
its account;

•an exchange distribution in accordance with the rules of the applicable
exchange;

•privately negotiated transactions;

•settlement of short sales;

•broker-dealers may agree with the Selling Stockholders to sell a specified
number of such shares at a stipulated price per share;

•a combination of any such methods of sale; and

•any other method permitted pursuant to applicable law.

        The Selling Stockholders may also sell shares under Rule 144 under the
Securities Act, if available, rather than under this prospectus.

        Broker-dealers engaged by the Selling Stockholders may arrange for other
brokers-dealers to participate in sales. Broker-dealers may receive commissions
or discounts from the Selling Stockholders (or, if any broker-dealer acts as
agent for the purchaser of shares, from the purchaser) in amounts to be
negotiated. The Selling Stockholders do not expect these commissions and
discounts to exceed what is customary in the types of transactions involved.

        The Selling Stockholders may from time to time pledge or grant a
security interest in some or all of the shares of common stock owned by them
and, if they default in the performance of their secured obligations, the
pledgees or secured parties may offer and sell the shares of common stock from
time to time under this prospectus, or under an amendment to this prospectus
under Rule 424(b)(3) or other applicable provision of the Securities Act of 1933
amending the list of Selling Stockholders to include the pledgee, transferee or
other successors in interest as Selling Stockholders under this prospectus.

        The Selling Stockholders and any broker-dealers or agents that are
involved in selling the shares may be deemed to be "underwriters" within the
meaning of the Securities Act in connection with such sales. In such event, any
commissions received by such broker-dealers or agents and any profit on the
resale of the shares purchased by them may be deemed to be underwriting
commissions or discounts under the Securities Act. The Selling Stockholders have
informed the Company that it does not have any agreement or understanding,
directly or indirectly, with any person to distribute the Common Stock.

        The Company is required to pay all fees and expenses incident to the
registration of the shares. The Company has agreed to indemnify the Selling
Stockholders against certain losses, claims, damages and liabilities, including
liabilities under the Securities Act.

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REGISTRATION RIGHTS AGREEMENT
ANNEX A
Plan of Distribution