RESPONSE TO SEQUENTIAL TREATMENT WITH LYMPHOBLASTOID INTERFERON-ALPHAIN PATIENTS WITH PH-LEUKEMIA UNRESPONSIVE TO RECOMBINANT INTERFERON-ALPHA (RIFN-ALPHA-2A) AND NEUTRALIZING-RIFN-ALPHA-2A ANTIBODIES NEGATIVE( CHRONIC MYELOID)

Nine Ph+ CML patients in chronic phase who were hematologically and/or karyotypically unresponsive to recombinant-IFN alpha 2a (rIFN alpha 2 a) and neutralizing-rIFN alpha 2a Abs negative were shifted from rIFN alpha 2a to lymphoblastoid-IFN alpha (IFN alpha-Ly) therapy. After 3 m onths of IFN alpha-Ly treatment, the hematologic response was reinduce d in 3 out of the 6 pts who were resistant to previous rIFN alpha 2a t herapy, and was maintained in 2 out of 3 patients who were hematologic ally but not karyotypically responsive to rIFN alpha 2a. After 6 and 1 2 months, the hematologic response was progressively lost, being prese nt only in 3 out of 7 and in 2 out of 3 evaluable patients respectivel y. None of the hematologically responsive patients achieved a karyotyp ic response (Ph neg, metaphases = O%). One patient, who was hematologi cally responsive, continued being treated with IFN alpha-ly for 36 mon ths but he did not achieve any karyotypic response. The results of thi s study suggest that in the unresponsive and neutralizing-rIFN alpha 2 a Abs negative CML patients a change in therapy, by using a non crossr eactive type of IFN alpha would not be advantageous. (C) 1997, Ferrata Storti Foundation.