Reverse transcriptase activity (RTA) in lymphocyte cultures of AIDS patients treated with HPA-23.

HPA-23 was used in a parallel, multiple dose study in patients with Centers for Disease Control (CDC)-defined AIDS. Sixteen patients were divided into four dosage groups, receiving 0.25, 0.5, 1.0, or 2.0 mg/kg HPA-23 respectively, by rapid IV infusion five days/week for eight weeks. Blood was collected before, at weeks 1, 3, and 7 of treatment, and two weeks post-therapy. Patient peripheral blood lymphocytes (PBL) were cultivated in the presence of fresh PBL from a healthy donor for 30 days. Media were changed and reverse transcriptase activity (RTA) was tested every four to five days. The results showed a significant decrease in RTA in patients treated with a dose of 0.5 or 1 mg/kg, but only a slight decrease in patients who received the lowest dose. In the group treated with the 2 mg/kg dose, two patients had toxic reactions and were discontinued; the other two showed a slight decrease in RTA. In 40% of treated patients, RTA did not increase again two weeks after the end of treatment. No significant immunologic and clinical changes were noticed during the observation period. In vitro experiments of Con A stimulated PBL in presence and absence of HPA-23 showed an increase in proliferation in the presence of the drug.