Vaccine Vigil

The National Institutes of Health launched a Phase II clinical trial in October of HVTN 205, an experimental preventive HIV vaccine that uses synthetic genes from strains A, B, and C of the virus, which account for 85% of the world's HIV cases. __________ Merck announced plans in September to double the enrollment in its clinical trial of MRKAd5--a preventive and therapeutic experimental HIV vaccine--after early study data showed that the vaccine boosted participants' CD4 cells to 50 to 100 times their baseline number. The vaccine uses a common cold virus to deliver key HIV genes into the body to stimulate the immune system to attack HIV.