definiens: shall mean any Drug Candidat e comprised of, modulating, interacting with, or derived from the same Collabor ation Target as another Drug Candidate ( including any Licensed Product ) comprise d of, modulating, interacting with, or derived from the same Collab oration Target . The adoption of an alternative to or replacement of any Drug Candidate may be due to factors that include such alternative ’s or replacement ’s possession of a bett er drug profile than the prior Drug Candidate, or toxicity issues, formulation pro blems, lack of efficacy, safety issues or any other factor having an adverse effect upon the ability to effectively develop or commercialize such prior Drug Candidate with the exercise of Commercially Reasonable Efforts . For the avoidance of doubt, no Drug Candidate comprised of, modulating, interacting with or deriv ed from NKG2A shall be a Backup Product for Anti -KIR