Patent ID: 8442776

Claim:
A method for designing a complement inhibitor, the method comprising: (a) obtaining a monoclinic crystal in space group P2 1 , having the unit cell dimension of a=85.8, b=124.7, c=127.4 Å, β=95.1°, of a complex consisting of C3c purified from human plasma and compstatin of SEQ ID NO:1 bound to the C3c at a compstatin binding location; (b) determining the three dimensional structure of the complex using the crystal obtained in (a) by the X-ray diffraction method to obtain the atomic coordinates of the structure; (c) providing on a computer the atomic coordinates of the three dimensional structure of the complex; and (d) utilizing a program operated by the computer to design a chemical compound predicted to bind to C3 or C3c at the compstatin binding location and inhibit proteolytic activation of C3.