Assessing Pretomanid for Tuberculosis (APT), a Randomized Phase 2 Trial of Pretomanid-Containing Regimens for Drug-Sensitive Tuberculosis: 12-Week Results.

Rationale: Pretomanid is a new nitroimidazole with proven treatment-shortening efficacy in drug-resistant tuberculosis. Pretomanid-rifamycin-pyrazinamide combinations are potent in mice but have not been tested clinically. Rifampicin, but not rifabutin, reduces pretomanid exposures. Objectives: To evaluate the safety and efficacy of regimens containing pretomanid-rifamycin-pyrazinamide among participants with drug-sensitive pulmonary tuberculosis. Methods: A phase 2, 12-week, open-label randomized trial was conducted of isoniazid and pyrazinamide plus 1) pretomanid and rifampicin (arm 1), 2) pretomanid and rifabutin (arm 2), or 3) rifampicin and ethambutol (standard of care; arm 3). Laboratory values of safety and sputum cultures were collected at Weeks 1, 2, 3, 4, 6, 8, 10, and 12. Time to culture conversion on liquid medium was the primary outcome. Measurements and Main Results: Among 157 participants, 125 (80%) had cavitary disease. Median time to liquid culture negativity in the modified intention-to-treat population (n = 150) was 42 (arm 1), 28 (arm 2), and 56 (arm 3) days (P = 0.01) (adjusted hazard ratio for arm 1 vs. arm 3, 1.41 [95% confidence interval (CI), 0.93-2.12; P = 0.10]; adjusted hazard ratio for arm 2 vs. arm 3, 1.89 [95% CI, 1.24-2.87; P = 0.003]). Eight-week liquid culture conversion was 79%, 89%, and 69%, respectively. Grade ≥3 adverse events occurred in 3 of 56 (5%), 5 of 53 (9%), and 2 of 56 (4%) participants. Six participants were withdrawn because of elevated transaminase concentrations (five in arm 2, one in arm 1). There were three serious adverse events (arm 2) and no deaths. Conclusions: Pretomanid enhanced the microbiologic activity of regimens containing a rifamycin and pyrazinamide. Efficacy and hepatic adverse events appeared highest with the pretomanid and rifabutin-containing regimen. Whether this is due to higher pretomanid concentrations merits exploration. Clinical trial registered with www.clinicaltrials.gov (NCT02256696).

Pretomanid Pharmacokinetics in the Presence of Rifamycins: Interim Results from a Randomized Trial among Patients with Tuberculosis.

Shorter, more potent regimens are needed for tuberculosis. The nitroimidazole pretomanid was recently approved for extensively drug-resistant tuberculosis in combination with bedaquiline and linezolid. Pretomanid may also have benefit as a treatment-shortening agent for drug-sensitive tuberculosis. It is unclear how and whether it can be used together with rifamycins, which are key sterilizing first-line drugs. In this analysis, data were pooled from two studies: the Assessing Pretomanid for Tuberculosis (APT) trial, in which patients with drug-sensitive pulmonary TB received pretomanid, isoniazid, and pyrazinamide plus either rifampin or rifabutin versus standard of care under fed conditions, and the AIDS Clinical Trials Group 5306 (A5306) trial, a phase I study in healthy volunteers receiving pretomanid alone or in combination with rifampin under fasting conditions. In our population pharmacokinetic (PK) model, participants taking rifampin had 44.4 and 59.3% reductions in pretomanid AUC (area under the concentration-time curve) compared to those taking rifabutin or pretomanid alone (due to 80 or 146% faster clearance) in the APT and A5306 trials, respectively. Median maximum concentrations (Cmax) in the rifampin and rifabutin arms were 2.14 and 3.35 mg/liter, while median AUC0-24 values were 30.1 and 59.5 mg·h/liter, respectively. Though pretomanid exposure in APT was significantly reduced with rifampin, AUC0-24 values were similar to those associated with effective treatment in registrational trials, likely because APT participants were fed with dosing, enhancing pretomanid relative bioavailability and exposures. Pretomanid concentrations with rifabutin were high but in range with prior observations. While pretomanid exposures with rifampin are unlikely to impair efficacy, our data suggest that pretomanid should be taken with food if prescribed with rifampin. (This study has been registered at ClinicalTrials.gov under identifier NCT02256696.).

Safety and immunogenicity of the HPV-16/18 AS04-adjuvanted vaccine in HIV-positive women in South Africa: a partially-blind randomised placebo-controlled study.

In developing countries, risk of human papillomavirus (HPV) infection may be increased by the high prevalence of human immunodeficiency virus (HIV) infection. We evaluated the safety and immunogenicity of the HPV-16/18 AS04-adjuvanted vaccine in HIV-infected women in South Africa. Asymptomatic HIV-positive women aged 18-25 years (N=120) were stratified by CD4⁺ T-cell count and randomised (1:1) to receive HPV-16/18 vaccine (Cervarix®; GlaxoSmithKline Vaccines) or placebo (Al[OH]3) at 0, 1 and 6 months (double-blind). HIV-negative women (N=30) received HPV-16/18 vaccine (open label). Anti-HPV-16/18 antibody and CD4⁺ T-cell responses, CD4⁺ T-cell count, HIV viral load, HIV clinical stage and safety were evaluated for 12 months. The safety and reactogenicity profile of the HPV-16/18 vaccine was comparable in HIV-positive and HIV-negative women. Irrespective of baseline HPV status, all HIV-positive and HIV-negative women who received the HPV-16/18 vaccine were seropositive for both HPV-16 and HPV-18 after the second vaccine dose (month 2) and remained seropositive for both antigens at month 12. Anti-HPV-16/18 antibody titres at month 12 remained substantially above levels associated with natural infection. The HPV-16/18 vaccine induced sustained anti-HPV-16/18 CD4⁺ T-cell responses in both HIV-positive and HIV-negative women. No impact of baseline CD4⁺ T-cell count or HIV viral load was observed on the magnitude of the immune response in HIV-positive women. In HIV-positive women, CD4⁺ T-cell count, HIV viral load and HIV clinical stage were unaffected by HPV-16/18 vaccine administration. In conclusion, the HPV-16/18 AS04-adjuvanted vaccine appears immunogenic and well-tolerated in women with HIV infection. Study ID: 107863/NCT00586339.