Shingles (herpes zoster) is a viral infection caused by reactivation of dormant varicella zoster, the virus that causes chicken pox. Shingles affects roughly 1 million patients in the US alone each year. And although the associated rash usually resolves in two to four weeks, patients can suffer from chronic neuropathic pain for months or years afterward. The current standard of care for herpes zoster is a 7-day course of antiviral medication, of which three are currently approved in the US (acyclovir, valacyclovir and famvir). Inhibitex hopes its drug, FV-100 will be the fourth. FV-100 was specifically designed to target varicella zoster, and it possesses robust activity against the virus in vitro. Its pharmacokinetic profile makes it suitable for once-daily dosing (while current alternatives must be administered 3 to 5 times per day). FV-100 has a lot going for itself and it entered phase II just last year, with the first direct evidence of clinical activity in patients expected in Q4 2010. Phase II was designed to show superiority to an active comparator, valacyclovir, which would be an impressive result. Even a finding of non-inferiority may be sufficient for market approval, if the results are confirmed in phase III. However, Inhibitex plans to seek a development partner for FV-100 in the near term, and thus cannot wait for phase III results. Thus, the future success of FV-100 (not to mention Inhibitex itself) hinges on a successful outcome in phase II. In our latest report, we discuss the rationale for FV-100, factors that could influence the drug’s chance for success in phase II, market considerations that will weigh on Inhibitex and its potential collaborators alike. Finally, current treatment options for shingles are clearly suboptimal – thus there is a need for a better drug. Can FV-100 be it?