Based on in vitro data suggesting that recombinant human granulocyte- macrophage colony-stimulating factor (rhGM-CSF) is capable of stimulating acute myeloid leukemia (AML) blast cells to become more sensitive to cell-cycle-specific drugs we conducted a phase I/II study in de novo AML patients (pts). rhGM-CSF (250 micrograms/m2/d, continuous intravenous infusion) was administered in 18 pts suffering from de novo AML in combination with standard induction chemotherapy (3 + 7 = daunorubicin 45 mg/m2 days 1 through 3, cytosine-arabinoside [Ara- C] 200 mg/m2 continuous infusion days 1 through 7). GM-CSF was started 48 or 24 hours before chemotherapy (prephase) in 14 pts. In four pts with high white blood cell counts (WBC) rhGM-CSF was started after chemotherapy-induced cell reduction (WBC less than 30,000/mm3). During prephase GM-CSF induced an increase in neutrophil and blast cell counts in 13 of 14 and 10 of 14 pts, respectively. In vivo recruitment of leukemic cells into drug-sensitive phases of the cell cycle could be demonstrated by multiparameter cell-cycle analyses in peripheral blood (n = 7) and bone marrow (n = 4) specimens. On day 14, complete aplasia was evident in 17 of 18 pts. GM-CSF was administered until recovery from chemotherapy-induced myelosuppression (absolute neutrophil counts, [ANC] greater than 500/mm3). Fifteen pts (83%) achieved complete remission, 12 did so with one cycle. A shorter duration of neutropenia was evident in these pts compared with historical controls (n = 39), (ANC greater than 500/mm3, day 22.5 +/- 3.4 v 25.2 +/- 3.7, P less than .05). Three pts achieved complete remission after a second cycle (same combination of rhGM-CSF and 3 + 7). Two pts died during bone marrow aplasia because of invasive pulmonary aspergillosis. Clinical side effects possibly related to GM-CSF, mainly fever, diarrhea, and weight gain were mild and tolerable (World Health Organization toxicity grade less than or equal to 2). Together, rhGM-CSF recruits kinetically quiescient AML cells in vivo to enter drug-sensitive phases of the cell cycle and promotes early myeloid recovery from aplasia after exposure to standard induction chemotherapy for AML.

Isolated thrombocytopenia occurs frequently in patients infected with HIV. Studies of mechanisms of thrombocytopenia and clinical response to therapy suggest that the thrombocytopenia is often antibody mediated (ITP). The best approach to treatment of these patients is uncertain in that the routine modalities (steroids, splenectomy, vinca alkaloids) that are used to increase the platelet count in patients with classic ITP are known to be immunosuppressive. We report here the results of intravenous gammaglobulin (IVGG) treatment of 22 patients with HIV-related acute and chronic ITP who had severe thrombocytopenia and bleeding symptoms. Only one patient had an opportunistic infection at the time of treatment. Eight patients were homosexual, eight had hemophilia, three were i.v. drug abusers, two children had congenital acquisition of HIV, and one was the wife of an HIV + i.v. drug abuser. The average pretreatment platelet count was 22,000/microliter (hemophiliacs were treated at higher platelet counts than were the other patients), and the mean peak platelet count measured on days 5 to 8 was 182,000/microliter. Nineteen of 22 patients had peak platelet counts greater than 50,000/microliter following IVGG and 17/22 had peak counts greater than 100,000/microliter. After the initial infusions, all but three refractory patients could maintain adequate platelet counts with IVGG alone infused no more often than once every 2 weeks. The outcomes for the 22 patients after multiple maintenance IVGG infusions were remission, 5; stable without therapy, 1; maintenance, 13; and refractory, 3. The eight hemophiliacs with ITP responded better than did the eight homosexual ITP patients; their mean peak platelet count was 227,000/microliter versus 142,000/microliter in the homosexuals. In summary, patients with HIV-related ITP without opportunistic infections responded well to IVGG, with peak platelet counts comparable to those of ITP patients not infected with HIV. IVGG may be a useful therapy of ITP in HIV+ patients, since it appears to be less immunosuppressive than are conventional therapies, and none of the 22 HIV+ patients developed an opportunistic infection while receiving IVGG alone.

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Based on in vitro data suggesting that recombinant human granulocyte- macrophage colony-stimulating factor (rhGM-CSF) is capable of stimulating acute myeloid leukemia (AML) blast cells to become more sensitive to cell-cycle-specific drugs we conducted a phase I/II study in de novo AML patients (pts). rhGM-CSF (250 micrograms/m2/d, continuous intravenous infusion) was administered in 18 pts suffering from de novo AML in combination with standard induction chemotherapy (3 + 7 = daunorubicin 45 mg/m2 days 1 through 3, cytosine-arabinoside [Ara- C] 200 mg/m2 continuous infusion days 1 through 7). GM-CSF was started 48 or 24 hours before chemotherapy (prephase) in 14 pts. In four pts with high white blood cell counts (WBC) rhGM-CSF was started after chemotherapy-induced cell reduction (WBC less than 30,000/mm3). During prephase GM-CSF induced an increase in neutrophil and blast cell counts in 13 of 14 and 10 of 14 pts, respectively. In vivo recruitment of leukemic cells into drug-sensitive phases of the cell cycle could be demonstrated by multiparameter cell-cycle analyses in peripheral blood (n = 7) and bone marrow (n = 4) specimens. On day 14, complete aplasia was evident in 17 of 18 pts. GM-CSF was administered until recovery from chemotherapy-induced myelosuppression (absolute neutrophil counts, [ANC] greater than 500/mm3). Fifteen pts (83%) achieved complete remission, 12 did so with one cycle. A shorter duration of neutropenia was evident in these pts compared with historical controls (n = 39), (ANC greater than 500/mm3, day 22.5 +/- 3.4 v 25.2 +/- 3.7, P less than .05). Three pts achieved complete remission after a second cycle (same combination of rhGM-CSF and 3 + 7). Two pts died during bone marrow aplasia because of invasive pulmonary aspergillosis. Clinical side effects possibly related to GM-CSF, mainly fever, diarrhea, and weight gain were mild and tolerable (World Health Organization toxicity grade less than or equal to 2). Together, rhGM-CSF recruits kinetically quiescient AML cells in vivo to enter drug-sensitive phases of the cell cycle and promotes early myeloid recovery from aplasia after exposure to standard induction chemotherapy for AML.