EXHIBIT 10.91

                          REGISTRATION RIGHTS AGREEMENT


         This REGISTRATION RIGHTS AGREEMENT (this "Agreement"), dated as of
April 4, 2006, is by and between VYTERIS HOLDINGS (NEVADA), INC., a Nevada
corporation (the "Company"), and SPENCER TRASK SPECIALTY GROUP, LLC, a Delaware
limited liability company (the "Investor").

         The Company has agreed, on the terms and subject to the conditions set
forth in the Note Purchase Agreement, dated as of April 4, 2006 (the "Note
Agreement"), to issue and sell to the Investor named therein the Note in the
form attached to the Note Agreement (the "Note").

         The Note is convertible into shares (the "Registrable Shares") of the
Company's common stock, par value $0.001 per share (the "Common Stock) in
accordance with its terms.

         In order to induce the Investor to enter into the Note Agreement, the
Company has agreed to provide certain registration rights under the Securities
Act of 1933, as amended (the "Securities Act"), and under applicable state
securities laws.

         In consideration of the Investor entering into the Note Agreement, and
other good and valuable consideration, the receipt and sufficiency of which are
hereby acknowledged, the parties agree as follows:

         1.     Piggyback Registration Statement. If, at any time, the Company
proposes to file any registration statement on Form S-1 or such other
appropriate form in accordance with the Securities Act of 1933, as amended (the
"Securities Act") for purposes of a public offering of securities of the Company
(including, but not limited to, registration statements relating to secondary
offerings of securities of the Company, but excluding registration statements
relating to employee benefit plans or with respect to corporate reorganizations
or other transactions under Rule 145 of the Securities Act or initial public
offerings) it will give written notice by facsimile or mail, at least five (5)
days prior to the filing of each registration statement, to the Investor of its
intention to do so. If the Investor notifies the Company within five (5) days
after receipt of any such notice of its desire to include any such securities in
such proposed registration statement, the Company shall afford the Investor the
opportunity to have any Registrable Securities registered under such
registration statement.

         2.     Obligations of the Company. In connection with the filing of any
registration statement herein, the Company shall:

                2.1    Prepare and file with the Securities and Exchange
Commission (the "SEC") such amendments and supplements to such registration
statement and the prospectus used in connection with such registration statement
as may be necessary to comply with the provisions of the Securities Act with
respect to the disposition of all securities covered by such registration
statement.


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                2.2    Furnish to the Investor such numbers of copies of a
prospectus, including a preliminary prospectus, in conformity with the
requirements of the Securities Act, and such other documents as they may
reasonably request in order to facilitate the disposition of Registrable
Securities owned by them.

                2.3    Use its best efforts to register and qualify the
securities covered by such registration statement under such other securities or
"blue sky" laws of such jurisdictions as shall be reasonably requested by the
Investor; provided, however, that the Company shall not be required in
connection therewith or as a condition thereto to qualify to do business or to
file a general consent to service of process in any such states or
jurisdictions.

                2.4    Notify the Investor at any time when a prospectus
relating thereto is required to be delivered under the Securities Act of the
happening of any event as a result of which the prospectus included in such
registration statement, as then in effect, includes an untrue statement of a
material fact or omits to state a material fact required to be stated therein or
necessary to make the statements therein not misleading in the light of the
circumstances then existing.

                2.5    Use its best efforts to cause all Registrable Securities
covered by such registration statement to be listed on each securities exchange
on which similar securities listed by the Company are then listed.

         3.     Obligations of the Investor.

                The Investor shall furnish to the Company such information
regarding the Investor, the number of Registrable Securities owned and proposed
to be sold by it, the intended method of disposition of such securities and any
other information as shall be required to effect the registration of the
Investor's Registrable Securities, and cooperate with the Company in preparing
the registration statement and in complying with the requirements of the
Securities Act.

         4.     Registration Expenses.

                The Company shall bear and pay all expenses incurred in
connection with any registration, filing or qualification of Registrable
Securities, including without limitation all registration, listing, filing and
qualification fees, printers and accounting fees, but excluding (i) underwriting
discounts and commissions relating to the Registrable Securities and (ii) legal
fees and disbursements of any and all counsel retained by the Investor.

         5.     Suspension of Effectiveness.

If the Company shall furnish to the Investor a certificate signed by the
President or Chief Executive Officer of the Company stating that, in the good
faith judgment of the Board of Directors of the Company, it is necessary to
suspend the effectiveness of any registration statement filed hereunder, the
Company shall have the right, exercisable two (2) times only in


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any consecutive twelve (12) month period, to suspend the effectiveness of the
registration statement with respect to such offering for a period of not more
than an aggregate of ninety (90) days per suspension.

         6.     Indemnification.

                6.1    To the extent permitted by law, the Company will
indemnify the Investor, its members, directors, officers, shareholders,
employees, agents and affiliates, legal counsel for the Investor, and each
person controlling the Investor within the meaning of the Securities Act, with
respect to which registration, qualification or compliance of Registrable
Securities has been effected pursuant to this Agreement, against any losses,
claims, damages, liabilities or actions in respect thereof (collectively,
"Damages"), arising out of or based on any untrue statement or alleged untrue
statement of a material fact contained in a Registration Statement filed
pursuant hereto, prospectus offering circular or other document, or any omission
or alleged omission to state therein a material fact required to be stated
therein or necessary to make the statements therein not misleading, or any
violation or alleged violation by the Company of the Securities Act, the
Securities Exchange Act of 1934, as amended (the "Exchange Act"), or any state
securities laws or any rule or regulation promulgated under such laws and
relating to action or inaction required of the Company in connection with any
such registration, qualification or compliance; and the Company will pay each
the Investor any legal and other expenses reasonably incurred by them in
connection with investigating or defending any such claim, loss, damage,
liability or action; provided, however, that the indemnity contained in this
Section 6.1 shall not apply to: (i) amounts paid in settlement of any such
Damages if settlement is effected without the consent of the Company (which
consent shall not unreasonably be withheld); (ii) any such Damages arising out
of or a based upon any untrue statement or omission based upon information
furnished to the Company by the Investor and stated to be for use in connection
with the offering of securities of the Company; or (iii) any such Damages
arising out of or based upon the Investor's failure to deliver a copy of the
registration statement or prospectus or any amendments or supplements thereto.

                6.2    To the extent permitted by law, the Investor will, if
Registrable Securities held by the Investor are included in the securities as to
which such registration, qualification or compliance is being effected pursuant
to this Agreement, indemnify the Company, each of its directors, officers,
shareholders, employees, agents and affiliates, each legal counsel and
independent accountant of the Company, each person who controls the Company
within the meaning of the Securities Act, and each other the Investor, each of
its directors, officers, shareholders, employees, agents and affiliates, legal
counsel, and each person controlling such other Purchaser within the meaning of
the Securities Act, against all Damages arising out of or based upon arising any
untrue statement or alleged untrue statement of a material fact contained in a
registration statement filed pursuant hereto, prospectus offering circular or
other document, or any omission or alleged omission to state therein a material
fact required to be stated therein or necessary to make the statements therein
not misleading, or any violation or alleged violation by the Investor of the
Securities Act, the Exchange Act, or any state securities laws or any rule or
regulation promulgated under such laws and relating to action or inaction
required of the Investor in connection with any such registration, qualification
or compliance; and the Investor will pay the Company or such other Investor any
legal and other expenses reasonably incurred by them in


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connection with investigating or defending any such claim, loss, damage,
liability or action, in each case, to the extent, but only to the extent, that
such untrue statement or alleged untrue statement or omission or alleged
omission is made in such registration statement, prospectus, offering circular
or other document in reliance on and in conformity with information furnished to
the Company by the Investor and stated to be for use in connection with the
offering of securities of the Company; provided, however, that the indemnity
contained in this Section 6.2 shall not apply to amounts paid in settlement of
any such Damages if settlement is effected without the consent of the Investor
(which consent shall not unreasonably be withheld).

                6.3    Promptly after receipt by an indemnified party under this
Section 6 of notice of the commencement of any action (including any
governmental action), such indemnified party will, if a claim in respect thereof
is to be made against any indemnifying party under this Section 6, deliver to
the indemnifying party a written notice of the commencement thereof and the
indemnifying party shall have the right to participate in, and, to the extent
the indemnifying party so chooses, jointly with any other indemnifying party
similarly noticed, to assume the defense thereof with counsel mutually
satisfactory to the parties; provided, however, that an indemnified party shall
have the right to retain one separate counsel, with the reasonable fees and
expenses to be paid by the indemnifying party, if representation of such
indemnified party by the counsel retained by the indemnifying party would be
inappropriate due to actual or potential differing interests between such
indemnified party and any other party represented by such counsel in such
proceeding. The failure to deliver written notice to the indemnifying party
within a reasonable time of the commencement of any such action, if prejudicial
to its ability to defend such action, shall relieve such indemnifying party of
any liability to the indemnified party under this Section 6, but the omission to
so deliver written notice to the indemnifying party will not relieve it of any
liability that it may have to any indemnified party otherwise than under this
Section 6.

                6.4    If the indemnification provided for in this Section 6 is
held by a court of competent jurisdiction to be unavailable to an indemnified
party with respect to any loss, liability, claim, damage or expense referred to
therein, then the indemnifying party, in lieu of indemnifying such indemnified
party hereunder, shall contribute to the amount paid or payable by such
indemnified party as a result of such Damages in such proportion as is
appropriate to reflect the relative fault of the indemnifying party on the one
hand and of the indemnified party on the other in connection with the statements
or omissions that resulted in such Damages as well as any other relevant
equitable considerations. The relative fault of the indemnifying party and of
the indemnified party shall be determined by reference to, among other things,
whether the untrue or alleged untrue statement of a material fact or the
omission or alleged omission to state a material fact relates to information
supplied by the indemnifying party or by the indemnified party and the parties'
relative intent, knowledge, access to information and opportunity to correct or
prevent such statement or omission.

                6.5    The obligations of the Company and the Investor under
this Section 6 shall survive the completion of any offering of Registrable
Securities pursuant to a registration statement under this Agreement.

         7.     Notices.


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                7.1    Any notice or communication required or permitted
hereunder shall be given in writing and shall be made by hand delivery, by
confirmed facsimile, by overnight courier or by registered or certified mail,
addressed (i) if to the Investor, to the Investor's address as set forth on
Schedule A hereto, and (ii) if to the Company, to Vyteris Holdings (Nevada),
Inc., 13-01 Pollitt Drive, Fair Lawn, New Jersey 07410, Attention: Chief
Executive Officer, Facsimile: (201) 796-6057 with a copy to Lownestein Sandler
PC, 65 Livinston Avenue, Roseland, NJ 07068, facsimile number (973) 597-2400,
Attention: Peter H. Ehrenberg, Esq.

                7.2    All such notices and other communications shall be deemed
to have been delivered and received (i) in the case of personal delivery or
facsimile, on the date of such delivery, (ii) in the case of overnight courier,
on the business day after the date when sent, and (iii) in the case of
registered or certified mail, on the third business day following such mailing.

         8.     Miscellaneous.

                8.1    This Agreement shall be governed by, and construed in
accordance with, the laws of the State of New York, without regard to the
principles of the conflict of laws thereof. The parties hereby irrevocably and
unconditionally consent to submit to the exclusive jurisdiction of the courts of
the State of New York located in New York County and any Federal court located
within New York County for any actions, suits or proceedings arising out of or
relating to this Agreement. The parties hereby irrevocably and unconditionally
waive any objection to the laying of venue of any action, suit or proceeding
arising out of this Agreement in the courts of the State of New York located in
New York County or the courts of the United States of America located in New
York County, and hereby further irrevocably and unconditionally waive and agree
not to plead or claim in any such court that any such action, suit of proceeding
brought in any such court has been brought in an inconvenient forum.

                8.2    Any term of this Agreement may be amended and the
observance of any term of this Agreement may be waived (either generally or in a
particular instance and either retroactively or prospectively), only with the
written consent of the Company and the Investor of a majority of the Registrable
Securities then outstanding. Any amendment or waiver effected in accordance with
this paragraph shall be binding upon the Investor of any Registrable Securities
then outstanding, each future Purchaser of all such Registrable Securities, and
the Company.

                8.3    Nothing in this Agreement, express or implied, is
intended to confer upon any party other than the parties hereto any rights,
remedies, obligations or liabilities under or by reason of this Agreement,
excepts as expressly provided herein.

                8.4    If one or more provisions of this Agreement are held to
be unenforceable under applicable law, such provision shall be excluded from
this Agreement and the balance of the Agreement shall be interpreted as if such
provision were so excluded and shall be enforceable in accordance with its
terms.

                8.5    The headings of the Sections of this Agreement are for
convenience and shall not by themselves determine the interpretation of this
Agreement.


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                8.6    This Agreement constitutes the entire contract among the
Company and the Investor relative to the subject matter hereof and supersedes in
its entirety any and all prior agreements, understandings and discussions with
respect thereto.

                8.7    The Agreement may be executed in two or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.



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



                                  SPENCER TRASK SPECIALTY GROUP, LLC


                                  By: /s/Donald F. Farley
                                      -------------------
                                     Name:  Donald F. Farley
                                     Title:  Chief Executive Officer


                                  VYTERIS HOLDINGS (NEVADA), INC.


                                  By: /s/Timothy J. McIntyre
                                      ----------------------
                                     Name: Timothy J. McIntyre
                                     Title:  President & Chief Executive Officer


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