The efficacy of recombinant human interferon a-2b (rh IFNa-2b) In the treatment of steroid resistant idiopathic thrombocytopenlc purpura (ITP) was studied In 50 cases.
Forty-one patients treated with rh IFNa-Pb three times a week, six of 18 (33.3%) In the low dose group (150 x lO'IU: 3 MIU) and four of 20 (20.0%) in the high dose group (300 x 1041U: 3 MIU) responded with platelet counts increasing to above 50 x 109/L. Because of the exacerbation of thrombocytopenla and nasal bleeding, treatment was discontinued wlthln 2 weeks In three patlents out of 41 cases. On the other hand, six of nine patients (66.7%) treated with 3 MIU of IFNa-Pb once a week for 8 weeks showed satisfactory response.
Treatment with either administration schedule did not result in sustaining platelet counts above 50 x 109R for a long time after treatment. The results Indicate that once a week administration schedule of rh IFNa-2b is more efficacious lor platelet counts increasing for short period in patients who failed to respond to steroid and other medlcatlons than other schedules. The maintenance of this treatment schedule will allow sustained increased platelet levels, resulting in relief of bleeding tendency, while also being cost effective In comparison with other IFN treatment schedules and achlevlng better patient compliance without flu-like symptoms.