I only know of Doctor Jacob Lalezari, from Quest Clinical Trials, as Rivil already mentioned, but I think that The Oasis Clinic on 27th st also has done a few, and that Dr is Dr Diana Sylvestre. Both her and Doctor J Lalezari are both Research Doctors~ good luck
Also if you have insurance Dr.Todd Frederick of CPMC is leading some trials.
Also Quest Clinical Trials in SF. The medical director is Dr.J. Laylezari.
try clinicaltrials.gov It has a pretty good search mechanism.