Addition of HPA 23 to cyclosporin in the treatment of thrombopenic purpura in HIV-positive subjects]

We associated HPA 23 (inhibitor of the reverse transcriptase) to cyclosporin A (CSA) for two homosexual patients with positive HIV serology, who had a peripheral thrombocytopenia resistant after alone CSA treatment. HPA 23 was given for 15 days at a dose of 4 mg/kg/day in a 24 hours continuous perfusion. The circulating tungsten blood concentration was about 4.4 micrograms/ml (between 3 and 8.4 micrograms/ml). Even if HPA 23 has frequently been responsible of thrombocytopenia at a dose superior than 2 mg/kg/day and in spite of any CSA activity in single treatment, this association shows a significant platelets increase. But thrombocytopenia reappeared a week after the stay of HPA 23 treatment. So, it is possible that HPA 23 might have, at this circulating blood concentration, an antiviral activity in vitro. In this hypothesis there might be a relation between antiviral replication and autoimmune disorders and, at least, CSA might oppose against the thrombocytopenia induced by HPA 23.