Innate Pharma

Regulatory Filings • Apr 12, 2013

INNATE PHARMA PRESENTS NEW DATA FOR PROPRIETARY PROGRAMS TARGETING TLR3 AND KIR3DL2

Marseille, France, April 12, 2013

Innate Pharma SA (Euronext Paris: FR0010331421 – IPH), the innate immunity company developing first-in-class drugs for cancer and inflammatory diseases, announces today that new preclinical data for two proprietary programs were presented at the Molecular Pattern Recognition Receptors meeting and the American Association for Cancer Research ("AACR") annual meeting:

• Dr Morel, Chief Business Officer of Innate Pharma, presented "Therapeutic Antibody against Toll-Like Receptor 3 for the Treatment of Inflammation", a comprehensive review of the IPH33 program, today, at the "Molecular Pattern Recognition Receptors" meeting in Boston, MA. Key conclusions are that humanized anti-TLR3 antibodies generated by Innate Pharma, following specific internalization in TLR3-expressing cells, showed efficient blocking of TLR3 signaling, with high potency. A surrogate anti-mouse TLR3-blocking antibody has shown activity in murine models of chronic obstructive pulmonary disease and colitis. This activity compares favorably to approved anti-inflammatory agents.

TLR3 is part of the Toll-like receptor (TLR) family and represents one of the Pattern Recognition Receptors used by the innate immune system. TLR3 is a major inducer of type I interferons and inflammatory cytokines such as IL-6. It is overexpressed on a specific subset of dendritic cells among immune cells, as well as on inflammatory epithelial cells. The IPH33 program aims at preventing inflammatory cytokine production, upstream of current treatments for inflammation.

Innate Pharma is validating this candidate for entry in regulatory preclinical development and intends to partner the further development of this program.

• Dr Sicard, Senior Director, R&D at Innate Pharma, presented a poster on IPH41 program: "Novel therapeutic and diagnostic antibodies against KIR3DL2, a unique tumor antigen overexpressed on subtypes of T Cell Lymphomas" on Wednesday April 10, 2013 at the AACR meeting in Washington D.C. The main conclusion is that in ex vivo patient samples, autologous NK cells can efficiently and selectively kill primary Sezary cells in presence of anti-KIR3DL2 antibodies as compared to alemtuzumab, a strongly lymphodepleting anti-CD52 antibody. Innate Pharma's anti-KIR3DL2 mAbs also showed activity in mice models of KIR3DL2+ tumor engraftment. In parallel, other antibodies were also developed as sensitive tools for the monitoring of KIR3DL2 as a biomarker in this patient population.

KIR3DL2 is a receptor naturally expressed on some NK cells and minor subpopulations of T cells. It is also aberrantly overexpressed on subtypes of T lymphomas/leukemias, such as Sezary Syndrome (SS), transformed Mycosis Fungoides (tMF) and HTLV-1+ Adult T Cell Leukemia.

Innate Pharma is in the process of selecting and validating the lead candidate for this program.

The full poster and presentation are available on the Company's website (www.innatepharma.com) in the section "Products in development".

About Innate Pharma:

Innate Pharma S.A. is a biopharmaceutical company developing first-in-class immunotherapy drugs for cancer and inflammatory diseases.

The Company specializes in the development of new monoclonal antibodies targeting receptors and pathways controlling the activation of innate immunity cells. Its innovative approaches have led to licensing agreements with Novo Nordisk A/S and Bristol-Myers Squibb.

Incorporated in 1999 and listed on NYSE-Euronext in Paris in 2006, Innate Pharma is based in Marseilles, France, and had 82 employees as at December 31, 2012.

Learn more about Innate Pharma at www.innate-pharma.com.

Practical Information about Innate Pharma shares:

ISIN code	FR0010331421
Ticker code	IPH

Disclaimer:

This press release contains certain forward-looking statements. Although the company believes its expectations are based on reasonable assumptions, these forward-looking statements are subject to numerous risks and uncertainties, which could cause actual results to differ materially from those anticipated. For a discussion of risks and uncertainties which could cause the company's actual results, financial condition, performance or achievements to differ from those contained in the forward-looking statements, please refer to the Risk Factors ("Facteurs de Risque") section of the Document de Reference prospectus filed with the AMF, which is available on the AMF website (http://www.amf-france.org) or on Innate Pharma's website.

This press release and the information contained herein do not constitute an offer to sell or a solicitation of an offer to buy or subscribe to shares in Innate Pharma in any country.

For additional information, please contact:

Innate Pharma ATCG Press

Laure-Hélène Mercier Director, Investor Relations Phone: +33 (0)4 30 30 30 87 Mob.: +33 (0)6 26 94 18 53 investors@innate-pharma.com mb@atcg-partners.com

Marielle Bricman