Human alpha-lymphoblastoid interferon. A phase I study including pharmacokinetics and effects on hematologic stem...

Human alpha lymphoblastoid interferon (Wellferon) was administered to 33 patients in a phase I study. Patients received Wellferon intramuscularly every 12 hours for 14 doses in nine dosage levels ranging from 0.75 X 10(6) units to 50.0 X 10(6) units. Toxicity tended to be dose dependent and included fever/chills, malaise, hematologic toxicity, and digestive tract toxicity. Thirty X 10(6) u q 12 h was felt to be the maximum tolerated dose. Three partial responses (renal cell carcinoma, diffuse histiocytic lymphoma, Hodgkin's disease) were achieved. Interferon rapidly (2 to 3 hours after the initial injection) reached peak serum levels which varied generally with dose and exceeded 500 u/ml at the 30 and 50 X 10(6) u dosages. Multiple doses of interferon resulted in cumulative peak levels substantially higher than first dose levels (greater than 500 u/ml at dosages greater than 3 X 10(6) u/ml and greater than 1,500 u/ml at dosages greater than or equal to 18 X 10(6) u). Interferon given at high dosages persisted up to 10 days beyond the final injection. Despite hematologic toxicity, inhibition of CFU-GM was not seen.