Vitamin D accelerates clinical recovery from tuberculosis: results of the SUCCINCT Study [Supplementary Cholecalciferol in recovery from tuberculosis]. A randomized, placebo-controlled, clinical trial of vitamin D supplementation in patients with pulmonary tuberculosis’

Randomized, placebo-controlled trial in adults with smear-positive, active pulmonary tuberculosis in Pakistan. Participants were enrolled from outpatient clinics at Aga Khan University Hospital and Ojha Institute of Chest Diseases, with 132 randomized to vitamin D and 127 to placebo; 119 in each arm completed follow-up.

Vitamin D3 (cholecalciferol) was given as 600,000 IU intramuscularly for 2 doses, 1 month apart, in addition to standard anti-tuberculosis therapy. The comparator was placebo plus standard therapy.

High-dose vitamin D accelerated clinical and radiographic recovery overall, although several secondary outcomes were not improved. In the vitamin D arm, weight gain was greater at 12 weeks (Δ 4.02 kg, p=0.007), BMI increased more (Δ 1.48, p=0.008), and chest X-ray improvement was greater (p=0.004). There was no significant effect on TB score (p=0.198), MUAC (p=0.079), smear conversion (81.8%; p=0.39), or MTBs-induced IFN-γ (3092 ± 1363 vs 2987 ± 1510; p=0.497). The authors concluded that therapeutic vitamin D may speed recovery in pulmonary TB, with immune benefits mainly in patients with deficient baseline vitamin D.

Follow-up was short at 12 weeks, so longer-term clinical effects and relapse prevention were not assessed. Several key outcomes were null, and the immune-response signal was not seen in the overall analysis. Generalizability is limited to adult smear-positive pulmonary TB patients in Pakistan receiving standard anti-TB therapy.