RhulL-2 adjunctive therapy in multidrug resistant tuberculosis: A comparison of two treatment regimens and placebo

Abstract

Setting: Low-dose recombinant human interleukin 2 (rhulL-2) adjunctive immunotherapy in multidrug resistant tuberculosis (MDR-TB) patients. Objective: Evaluation of the effects of daily versus pulse-administered rhulL-2 compared to placebo. Design: MDR-TB patients on best available antituberculous chemotherapy received rhulL-2 for 30 consecutive days (daily therapy), or for 5 days followed by a 9-day ‘rest’, for three cycles (pulse therapy). Placebo control patients received diluent. The cumulative total dose of rhulL-2 given to each patient in either rhulL-2 treatment group was the same. Patient immunologic, microbiologic, and radiologic responses were compared. Results: The three treatment schedules induced different results. Immune activation was documented in patients receiving daily rhulL-2 therapy. Numbers of CD25 + and CD56 + cells in the peripheral blood were increased in these patients, but not in patients receiving pulse rhulL-2 or placebo. In addition, 5 8 (62%) patients receiving daily rhulL-2 demonstrated reduced or cleared sputum bacterial load while only 2 7 (28%) pulse rhulL-2 treated and 2 8 (25%) controls showed bacillary clearance. Chest radiographs of 7 12 (58%) patients receiving daily rhulL-2 indicated significant improvement over 6 weeks. Only 2 9 (22%) pulse rhulL-2-treated patients and 5 12 (42%) placebo controls showed radiologic improvement. Conclusion: Daily low dose rhulL-2 adjunctive treatment stimulates immune activation and may enhance the antimicrobial response in MDR-TB.