EXHIBIT 1.1 FORM OF UNDERWRITING AGREEMENT IDENIX PHARMACEUTICALS, INC. COMMON STOCK (PAR VALUE $0.001 PER SHARE) UNDERWRITING AGREEMENTUnderwriting Agreement • July 6th, 2004 • Idenix Pharmaceuticals Inc • Pharmaceutical preparations • New York
Contract Type FiledJuly 6th, 2004 Company Industry Jurisdiction
CONFIDENTIAL Confidential Materials omitted and filed separately with the Securities and Exchange Commission. Asterisks denote omissions. STOCK PURCHASE AGREEMENTStock Purchase Agreement • July 6th, 2004 • Idenix Pharmaceuticals Inc • Pharmaceutical preparations • New York
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BETWEENLicense Agreement • July 6th, 2004 • Idenix Pharmaceuticals Inc • Pharmaceutical preparations • Massachusetts
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AGREEMENTCollaboration Agreement • July 6th, 2004 • Idenix Pharmaceuticals Inc • Pharmaceutical preparations • New York
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BETWEENCooperative Agreement • July 6th, 2004 • Idenix Pharmaceuticals Inc • Pharmaceutical preparations
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Dipartimento di Biologia Sperimentale "Bernardo Loddo" dell'Universita di Cagliari CittadellaUniversitaria SS 554 KM 4.5 09133 Monserrato (Cagliari) Dear Sir: Co-operative Antiviral Research Activity Agreement With reference to the Co-operative...Co-Operative Antiviral Research Activity Agreement • July 6th, 2004 • Idenix Pharmaceuticals Inc • Pharmaceutical preparations
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BY AND AMONGDevelopment, License and Commercialization Agreement • July 6th, 2004 • Idenix Pharmaceuticals Inc • Pharmaceutical preparations • New York
Contract Type FiledJuly 6th, 2004 Company Industry Jurisdiction
AGREEMENTCollaboration Agreement • July 6th, 2004 • Idenix Pharmaceuticals Inc • Pharmaceutical preparations
Contract Type FiledJuly 6th, 2004 Company Industry