Phase I/II study of intermittent all-trans-retinoic acid, alone and in combination with interferon alfa-2a, in patients with epidemic Kaposi's sarcoma.

PURPOSE: A phase I/II study of oral all-trans-retinoic acid (ATRA; tretinoin), administered every other week alone and then in combination with interferon (IFN) alfa-2a, was undertaken to evaluate the activity, toxicity, and pharmacokinetics of this regimen in patients with human immunodeficiency virus (HIV)-associated Kaposi's sarcoma (KS). PATIENTS AND METHODS: Thirteen patients with HIV-associated KS, eight of whom had more than 100 CD4 cells/microL, were entered. The protocol initially called for patients to receive 150 mg/m2/d of ATRA every other week. However, this regimen was associated with headaches, and the initial dose of ATRA was reduced to 40 mg/m2/d orally in three divided doses, increasing to a maximum of 100 mg/m2/d. After 12 weeks, IFN alfa-2a could be added. RESULTS: The principal toxicities from ATRA were headaches (12 patients) and dry skin or lip (seven patients). Of 12 assessable patients, 10 had progressive disease and two had stable disease on ATRA alone. One of eight assessable patients who went on to receive ATRA plus IFN alfa-2a had partial response (PR). There were no overall changes in the serum HIV p24 antigen (Ag) level or CD4 count during treatment with ATRA alone. Peak ATRA levels decreased during the week of continuous ATRA therapy, but rebounded when treatment was resumed after a week without the drug. CONCLUSION: Intermittent ATRA therapy was reasonably well tolerated and provided a means to circumvent the low plasma exposure found with continuous ATRA therapy. However, we were unable to document antitumor activity in patients with HIV-associated KS.

Pharmacokinetics of all-trans-retinoic acid administered on an intermittent schedule.

PURPOSE: Administration of all-trans-retinoic acid (ATRA) on a continuous daily schedule results in a rapid and sustained decrease in plasma drug concentrations. This pharmacokinetic study was performed to determine if administration of ATRA on an intermittent schedule could overcome the rapid decrease in plasma drug concentration and provide repetitive periods of higher plasma drug exposure. MATERIALS AND METHODS: ATRA was administered on repetitive cycles of 7 consecutive days of drug followed by 7 days without drug. On the days of pharmacokinetic monitoring, following an overnight fast, a fixed single oral dose of 40 mg/m2 was administered and frequent plasma samples were obtained over 8 hours. Patients had pharmacokinetic studies performed on the first and seventh days of the first week, and on the first day of the third and eleventh weeks. ATRA was measured in plasma with a reverse-phase high-performance liquid chromatography (HPLC) assay. RESULTS: Plasma exposure to ATRA as measured by the area under the plasma concentration-time curve (AUC) decreased significantly during the first week of drug administration, from a mean of 145 +/- 26 mumol/L.min on day 1 to 18 +/- 4 mumol/L.min by day 7. Plasma ATRA concentrations at the start of weeks 3 and 11 of this every-other-week schedule were equivalent to those achieved on day 1 of treatment, with mean AUCs of 177 +/- 39 and 128 +/- 30 mumol/L.min, respectively. CONCLUSION: An intermittent schedule of ATRA administration results in repetitive periods of exposure to concentrations of ATRA normally only observed on the first day of treatment. Phase II trials to evaluate the role of intermittent schedules of administration for ATRA are planned.

Pilot study of the immunologic effects of recombinant human growth hormone and recombinant insulin-like growth factor in HIV-infected patients.

OBJECTIVE: To study the immunologic effects of recombinant human growth hormone (rhGH), recombinant human insulin-like growth factor type 1 (rhIGF-1), or the combination, in patients with moderately advanced HIV infection. DESIGN: Randomized but not blinded trial. SETTING: Government medical research center. PATIENTS: Twenty-four HIV-infected patients with CD4 cell counts of 100-400 x 10(6)/l who were receiving nucleoside antiretroviral therapy. INTERVENTIONS: Either rhGH, rhIGF-1, or the combination was administered subcutaneously for 12 weeks. MAIN OUTCOME MEASURES: Immunologic parameters, including T-cell subsets and assays of in vitro interleukin (IL)-2 production in response to antigens and mitogens, and safety profile. RESULTS: Plasma IGF-1 levels were low or low-normal prior to treatment and increased with all three therapies. There were no significant changes in CD4 cell counts, RA/RO CD4 cell subsets, natural killer cell function, immunoglobulin levels, or in vitro IL-2 production in response to mitogen or alloantigens. However, there was an upward trend (and for p18IIIB a statistically significant increase) in the in vitro IL-2 production in response to each of five HIV envelope peptides. Potential toxic effects included fatigue, arthralgia, edema, myalgia, and headache. Patients also were noted to have weight gain averaging 4 kg early in the course of treatment. CONCLUSIONS: These results suggest that treatment with rhGH/rhIGF-1 was reasonably well tolerated and that modest improvement in HIV-specific immune function was attained. Further studies will help clarify the therapeutic potential of rhGH/rhIGF-1 as an immunostimulator in the setting of HIV infection.

Vertebral alterations in Scheuermann's kyphosis.

In a cadaver-derived skeletal collection of 1,384 thoracolumbar spinal columns, 103 (7.4%) individuals with vertebral changes of Scheuermann's kyphosis were identified. Anterior extension of the vertebral specimens was noted in 94% of affected specimens. No evidence of osteoporosis was noted by single-photon absorptiometric analysis in the affected sample compared with a normal control group. Biopsy specimens from two immature patients obtained at surgery suggested disorganized endochondral ossification similar to that noted in Blount's disease. It was concluded that increased pressure on the anterior margin of the centrum is responsible for histologic and morphologic changes of Scheurermann's kyphosis.