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                                                                    EXHIBIT 10.1

                      THIRD AMENDMENT TO LICENSE AGREEMENT

     This Amendment to License Agreement ("Amendment") is entered into as of
August 26, 2002, by and between BUKWANG PHARM. CO., LTD., with its principal
offices at 398-01, Daebang-Dong, Dongjak-Ku, Seoul 156-811, Korea ("Bukwang")
and TRIANGLE PHARMACEUTICALS, INC., with its principal offices located at 4
University Place, 4611 University Drive, Durham, North Carolina 27707
("Triangle") and amends certain terms of that certain License Agreement, dated
as of February 27, 1998, between Bukwang and Triangle, as amended April 1, 1999
and September 5, 2000 (the "Agreement"). Capitalized terms not defined herein
shall have the meanings given them in the Agreement.

                                    RECITALS

     A.   Bukwang and Triangle have previously entered into the Agreement,
pursuant to which Bukwang has licensed certain patent rights and know-how to
Triangle relating to a compound known as L-FMAU (also known as clevudine).

     B.   Triangle has certain diligence obligations with respect to the
clinical development of a Licensed Product.

     C.   Bukwang and Triangle desire to amend and clarify certain terms of the
Agreement relating to milestone payments and diligence obligations and the
calculation of Net Sales.

     NOW, THEREFORE, for good and valuable consideration, Triangle and Bukwang
hereby agree as follows:

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          1.   AMENDMENTS. The Agreement is hereby amended as follows:

          (a)  Section 1.23. Delete Section 1.22 and replace it with the
     following:

               "NDA" shall mean a New Drug Application or its equivalent filed
          in the U.S., China, Japan, Taiwan or, in the case of Europe, with the
          European Agency for the Evaluation of Medicinal Products."

          (b)  SECTION 1.24. Delete Section 1.24 and replace it with the
     following:

               "'Net Sales' of Licensed Products which contain as their active
          ingredients one or more Compounds and other compounds (a 'Combination
          Product') shall mean the portion of the gross sales price of such
          Combination Product attributable to the Compounds contained therein,
          billed by Triangle, its Affiliates or sublicensees to independent
          customers, including any consideration received, directly or
          indirectly, from such customers in respect of the sale, distribution
          or transfer of Licensed Products, less all the allowances,
          adjustments, reductions, discounts, taxes, duties, rebates and other
          items referred to in Section 1.23. The "portion of the gross sales
          price of such Combination Product attributable to the Compounds
          contained therein" shall be determined on a country-by-country basis
          and shall mean, in each country, the average gross sales price per
          gram of a Compound in the most comparable stock keeping unit of a
          Licensed Product having a Compound as the sole active ingredient in
          that country multiplied by the total number of grams of Compound
          contained in the Combination Product billed in that country during
          such royalty period.

               In the event that a Combination Product containing a Compound and
          one other active ingredient is sold in a country before a Licensed
          Product containing only one or more Compounds is sold in that country,
          the portion of gross sales price of such Combination Product
          attributable to Compounds until a Licensed Product containing only one
          or more Compounds as active ingredients is sold in that country shall
          be *** percent. In the event that a Combination Product containing a
          Compound and two or more other compounds as active ingredients is sold
          in a country before a Licensed Product containing only one or more
          Compounds is sold in that country, the portion of gross sales price of
          such Combination products attributable to Compounds until a Licensed
          Product containing only one or more Compounds as active ingredients is
          sold in that country shall be the percentage determined by ***.

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               In the event that Triangle or its Affiliates or sublicensees
          distribute any Licensed Products to a third party for non-monetary
          consideration (e.g. barter or exchange), such distribution shall be
          considered a sale for accounting and royalty purposes. Net Sales for
          any such distributions shall be determined on a country-by-country
          basis and shall be the average price of 'arm's length' sales by
          Triangle or its Affiliates or sublicensees in such country in the
          Territory during the royalty period in which such sale occurs or, if
          no such 'arm's length' sales occurred in such country in the Territory
          during such royalty period, during the last royalty period in which
          such 'arm's length' sales occurred. If no 'arm's length' sales have
          occurred in a particular country in the Territory, Net Sales for any
          such distributions in such country in the Territory, shall be the
          average price of 'arm's length' sales in all countries in the
          Territory during such royalty period."

          (c)  SECTION 1.25. Delete Section 1.25 and replace it with the
     following:

               "'Phase II Completion Date' shall mean sixty (60) days after the
          completion of statistical analyses of the final results of those Phase
          II clinical trials which Triangle considers reasonably necessary for
          purposes of inclusion in an NDA for approval of a Licensed Product for
          HBV. As used in the preceding sentence, 'Phase II clinical trials'
          shall mean those well-controlled clinical trials sponsored by Triangle
          or Bukwang, the primary objective of which is to ascertain additional
          data regarding the safety and tolerance of a Licensed Product and
          preliminary data regarding such Licensed Product's antiviral effects
          against HBV."

          (d)  SECTION 1.26. Delete Section 1.26 and replace it with the
     following:

               "'Phase III Completion Date' shall mean sixty (60) days after the
          completion of statistical analyses of the final results of those
          Phase  III  clinical  trials  which  Triangle   considers   reasonably
          necessary  for  purposes  of  inclusion  in an NDA for  approval  of a
          Licensed  Product for HBV. As used in the preceding  sentence,
          'Phase III clinical trials' shall mean those well-controlled  clinical
          trials  sponsored  by Triangle or Bukwang,  the primary  objective  of
          which  is to  ascertain  definitive  safety  data  and  efficacy  data
          regarding  such  Licensed  Product's  antiviral  effects  against  HBV
          sufficient to support an NDA.

          (e)  SECTION 3.2.

               (i)  Delete Section 3.2(a)(vi) and replace it with the following:

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               "(vi) ***

               (ii) Add the following after the Milestone and Milestone Payment
          chart in Section 3.2(a):

               "(1) If the Milestone Payment identified in item (iii) above has
               not been paid by *** and Triangle has not given notice of
               termination of this Agreement prior to such date, Triangle will
               pay Bukwang *** , such amount to be credited against the
               Milestone Payment due on ***.

               (2)  The balance *** of the Milestone Payment due on *** shall be
                    paid to Bukwang upon the first to occur of *** or *** .

               (3)  If the Milestone Payment identified in item (iv) above has
               not been paid by *** and Triangle has not given notice of
               termination of this Agreement prior to such date, Triangle will
               pay Bukwang *** , such amount to be credited against the
               Milestone Payment due on *** .

               (4)  The balance *** of the Milestone Payment due on ***shall be
                    paid to Bukwang upon the first to occur of *** or ***."

          (f)  SUBSECTIONS 6.2(a)(i) AND 6.2(a)(ii). Delete Subsections
     6.2(a)(i) and 6.2(a)(ii) and replace them as follows:

                    "(i) files what it reasonably believes to be a complete NDA
               for a Licensed Product for HBV within *** after the Effective
               Date; provided, however, said *** period shall be subject to up
               to *** extensions of *** each, at Triangle's election, by payment
               to Bukwang of a sum of *** for each *** extensions, *** for each
               *** extensions and *** for each *** extensions; and"

                    "(ii) "files an NDA for a Licensed Product containing the
               Compound as its sole active ingredient no later than the same
               time as Triangle files an NDA for a Combination Product; and"

          (f)  SUBSECTION 6.2(a)(iii). A new Subsection 6.2(a)(iii) shall be
               inserted as follows:

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                    "(iii) commercially introduces, or causes its Affiliates or
               sublicensees to commercially introduce, any Licensed Product
               (including any Licensed Product containing the Compound as its
               sole active ingredient) approved in any country in which an NDA
               has been filed within *** of Registration of such Licensed
               Product in such country."

          (g)  SECTION 7.3. Delete the word "and" at the end of Subsection
     7.3(b). Delete the period at the end of Subsection 7.3(c) and insert ";
     and" and add the following Subsection 7.3(d):

               "(d) evaluating all preclinical and clinical data in order to
               assess the optimal dose of Licensed Products containing the
               Compound as its sole active ingredient or containing the Compound
               as one active ingredient in Combination Product to be used in
               Phase III clinical studies to support Registration of Licensed
               Products."

     2.   GENERAL TERMS. The Agreement, as amended by this Amendment,
constitutes the entire agreement between Bukwang and Triangle or regarding the
subject matters contained therein and herein. In the event of any conflict
between the provisions of the Agreement and this Amendment, the provisions of
this Amendment shall govern and control. This Amendment shall be governed by,
and construed in accordance with, the laws of the State of Georgia without
regard to its conflicts of laws principles. This Amendment may be executed in
any number of counterparts, each of which shall be deemed an original and all of
which shall constitute one and the same instrument. If any provision of this
Amendment is for any reason held to be ineffective, unenforceable or illegal,
such condition shall not affect the validity or enforceability of any of the
remaining portions hereof; provided, further, that the parties shall negotiate
in good faith to replace any ineffective, unenforceable or illegal provision
with an effective replacement as soon as is practical.

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     IN WITNESS WHEREOF, Bukwang and Triangle have each executed this Amendment
through an authorized officer as of the date written below.

                                         BUKWANG PHARM. CO., LTD.

                                         By:    /s/ S.K. Lee
                                                ------------------------------
                                         Its:   Executive Managing Director
                                                ------------------------------
                                         Date:  August 27, 2002
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                                         TRIANGLE PHARMACEUTICALS, INC.

                                         By:    /s/ R. Andrew Finkle
                                                ------------------------------
                                         Its:   Executive Vice President
                                                ------------------------------
                                         Date:  August 26, 2002
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