As further inducement for the Landlord to enter into the Fifth Amendment, on December 16, 2010, the Company entered into a Stock Purchase Agreement (the “Purchase Agreement”) with BioMed Realty, L.P. (“BioMed”), the sole member of the Landlord, pursuant to which the Company agreed to issue to BioMed an aggregate of 2,115,727 shares (the “Shares”) of the common stock, par value $0.006 per share, of the Company. The Purchase Agreement provides BioMed with certain piggyback registration rights with respect to the Shares, which rights continue until such time as the Shares may be sold publicly without restriction under the Securities Act of 1933, as amended (the “Securities Act”), including in reliance on Rule 144 promulgated thereunder.