SOLAR SIMULATOR-INDUCED HERPES-SIMPLEX LABIALIS - USE IN EVALUATING TREATMENT WITH ACYCLOVIR PLUS 348U87

Models of UV radiation induced herpes labialis utilizing crude light s ources have previously been used to examine the efficacy of antivirals . We sought to improve upon this model by using a solar simulator. Ini tial studies revealed that 13 of 34 (38%) subjects with a history of r ecurrent HSV labialis receiving three minimal erythema doses (MED's) o f UV light developed herpes labialis. We next evaluated the effects of combined therapy with topical ACV and 348U87, a ribonucleotide reduct ase inhibitor, begun immediately after UV exposure for the prevention and treatment of herpes labialis. No significant reduction in the inci dence or severity of herpes labialis was detected although the study w as terminated after the interim analysis revealed no benefit, thus red ucing the power to detect a difference. This lack of effect may be exp lained by the general poor efficacy of topical treatment for recurrent HSV infection. Further studies of ACV + 348U87 in vehicles that shoul d increase the penetration and stability of the drugs are planned.