ASSIGNMENT AND TERMINATION AGREEMENT

ASSIGNMENT AND TERMINATION AGREEMENT

This Assignment and Termination Agreement, (the “ Agreement ”), effective as of June 2, 2009 (the “ Effective Date ”), is by and between CombinatoRx, Incorporated (“ CRX-US ”), 245 First Street, Cambridge, MA 02142, U.S.A., CombinatoRx (Singapore) Pte. Ltd. (“ CRX-SG ”), 11 Biopolis Way, Helios #08-05, Singapore 138667 and the Liverpool School of Tropical Medicine

(“ LSTM ”), Pembroke Place, Liverpool, L3 5QA, United Kingdom. CRX-US, CRX-SG and

LSTM are collectively referred to as (the “ Parties ”) or individually as (any “ Party ”).

WHEREAS , CRX-US and CRX-SG are each a party to a Consortium Agreement effective as of April 1, 2008 (the “ Consortium Agreement ”) by and between LSTM, the Institute for Medical Microbiology, Immunology and Parasitology, University of Bonn, the Tropical Parasitic Diseases Unit of Northwick Park Institute for Medical Research, TRS Labs, Inc. and New England Biolabs, Inc. (collectively, the “ AWOL Consortium ”) by way of an Accession Agreement between the Parties, dated October 8, 2008 (the “ Accession Agreement ”);

WHEREAS , the Parties are each a party to a Co-Ownership Agreement, dated October 8, 2008 (the “ Co-Ownership Agreement ”) and a Project Agreement, dated October 8, 2008 (the “ Project Agreement ”), which collectively with the Consortium Agreement and Accession Agreement constitute the “ A-WOL Agreements ”; and

WHEREAS , on or before the Effective Date, CRX-US is divesting its entire ownership interest in its subsidiary CRX-SG, and in connection with such transaction, the Parties desire for CRX-SG to continue as a member of the A-WOL Consortium and remain bound by the rights and responsibilities set forth in the A-WOL Agreements, and for CRX-US to no longer be a member of the A-WOL Consortium and be bound by the A-WOL Agreements after the Effective Date.

NOW, THEREFORE , the CRX-US, CRX-SG and LSTM (for itself and on behalf of the A-WOL Consortium), hereby agree as follows: