pyrazinamide
Regulatory sources consulted
Approved indications
- Initial phase of susceptible active tuberculosis, always combined with other antitubercular drugs.
Contraindications
Absolute
- Severe liver disease, severe renal impairment, hyperuricemia, and porphyria according to the label.
Clinical warnings
- It may cause severe hepatotoxicity; obtain baseline and periodic liver tests and discontinue with injury. — CIMA/AEMPS, ficha técnica 43418
- Major warning · It may raise uric acid and precipitate gout; monitor joint symptoms and glucose in people with diabetes. — CIMA/AEMPS, ficha técnica 43418
Drug interactions
- HighIsoniazid, rifampin, or other hepatotoxic drugs
Mechanism: Liver-injury risk may be additive.
Recommendation: Use only within the indicated regimen with close liver monitoring.
CIMA/AEMPS, ficha técnica 43418
- HighProbenecid
Mechanism: It may further increase uric acid and worsen gout.
Recommendation: Monitor uric acid and gout symptoms.
CIMA/AEMPS, ficha técnica 43418
- HighCyclosporine
Mechanism: Pyrazinamide may reduce cyclosporine concentrations.
Recommendation: Monitor cyclosporine concentrations and efficacy and adjust if needed.
CIMA/AEMPS, ficha técnica 43418
Adverse events
Common (≥1%)
Hyperuricemia, arthralgia, nausea, and increased transaminases
Rare but serious
Hepatitis, acute gout, and severe skin reactions
Pregnancy and lactation
Use during pregnancy if the antitubercular regimen requires it and benefit outweighs risk. Weigh breastfeeding with the care team.
Recent literature (PubMed)
For decades, poor treatment options and low-quality evidence plagued care for patients with rifampin-resistant tuberculosis. The advent of new drugs to treat tuberculosis and enhanced funding now permit randomized, controlled trials of shortened-duration, all-oral treatments for rifampin-resistant tuberculosis. We conducted a phase 3, multinational, open-label, randomized, controlled noninferiority trial to compare standard therapy for treatment of fluoroquinolone-susceptible, rifampin-resistant tuberculosis with five 9-month oral regimens that included various combinations of bedaquiline (B), delamanid (D), linezolid (L), levofloxacin (Lfx) or moxifloxacin (M), clofazimine (C), and pyrazinamide (Z). Participants were randomly assigned (with the use of Bayesian response-adaptive randomization) to receive one of five combinations or standard therapy. The primary end point was a favorable outcome at week 73, defined by two negative sputum culture results or favorable bacteriologic, clinical, and radiologic evolution. The noninferiority margin was -12 percentage points. Among the 754 participants who underwent randomization, 699 were included in the modified intention-to-treat analysis, and 562 in the per-protocol analysis. In the modified intention-to-treat analysis, 80.7% of the patients in the standard-therapy group had favorable outcomes. The risk difference between standard therapy and each of the four new regimens that were found to be noninferior in the modified intention-to-treat population was as follows: BCLLfxZ, 9.8 percentage points (95% confidence interval [CI], 0.9 to 18.7); BLMZ, 8.3 percentage points (95% CI, -0.8 to 17.4); BDLLfxZ, 4.6 percentage points (95% CI, -4.9 to 14.1); and DCMZ, 2.5 percentage points (95% CI, -7.5 to 12.5). Differences were similar in the per-protocol population, with the exception of DCMZ, which was not noninferior in that population. The proportion of participants with grade 3 or higher adverse events was similar across the r
Tuberculosis (TB) remains a leading cause of infectious death worldwide, and poverty is a major driver. Clinically, TB presents as "latent" TB and active TB disease, and the treatment for each is different. TB drugs can display "early bactericidal activity (EBA)" and / or "sterilizing activity" (clearing persisters). Isoniazid is excellent at the former, and rifampin is excellent at the latter. Pyrazinamide and ethambutol complete the first-line regimen for drug-susceptible TB, each playing a specific role. Drug-resistant TB is an increasing concern, being met, in part, with repurposed drugs (including moxifloxacin, levofloxacin, linezolid, clofazimine, and beta-lactams) and new drugs (including bedaquiline, pretomanid, and delamanid). One challenge is to select drugs without overlapping adverse drug reaction profiles. QTc interval prolongation is one such concern, but to date, it has been manageable. Drug penetration into organism sanctuaries, such as the central nervous system, bone, and pulmonary TB cavities remain important challenges. The pharmacodynamics of most TB drugs can be described by the area under the curve (AUC) divided by the minimal inhibitory concentration (MIC). The hollow fiber infection model (HFIM) and various animal models (especially mouse and macaque) allow for sophisticated pharmacokinetic/pharmacodynamic experiments. These experiments may hasten the selection of the most potent, shortest possible regimens to treat even extremely drug resistant TB. These findings can be translated to humans by optimizing drug exposure in each patient, using therapeutic drug monitoring and dose individualization.
Tuberculous meningitis is often lethal, and many survivors have disabilities despite antimicrobial treatment and adjunctive glucocorticoid therapy. Standard-dose rifampin has limited central nervous system penetration. Whether high-dose rifampin could improve survival outcomes is unknown. We performed a double-blind, randomized, placebo-controlled clinical trial involving adults with tuberculous meningitis in Indonesia, South Africa, and Uganda. We assigned persons with and those without human immunodeficiency virus (HIV) coinfection to receive standard daily isoniazid, rifampin (at a dose of 10 mg per kilogram of body weight), ethambutol, and pyrazinamide plus either additional rifampin (for a cumulative dose of 35 mg per kilogram; high-dose group) or matched placebo (standard-dose group) for 8 weeks; participants in both groups received standard therapy for the remainder of the 9-to-12-month treatment course. The primary outcome was 6-month mortality. A total of 499 participants were included in the intention-to-treat population (249 randomly assigned to the high-dose group and 250 to the standard-dose group), of whom 304 (60.9%) were persons living with HIV and 428 (85.8%) had definite or probable tuberculous meningitis. During 6 months of follow-up, 109 participants (Kaplan-Meier estimate, 44.6%) in the high-dose group and 100 participants (Kaplan-Meier estimate, 40.7%) in the standard-dose group died (hazard ratio, 1.17; 95% confidence interval, 0.89 to 1.54; P = 0.25). Among the participants who died within 6 months, the median time to death was 13 days (interquartile range, 4 to 39) in the high-dose group and 24 days (interquartile range, 6 to 56) in the standard-dose group. Drug-induced liver injury occurred in 8.0% of the participants in the high-dose group and in 4.4% of those in the standard-dose group, but no deaths from drug-induced liver injury occurred. Among persons with tuberculous meningitis, no evidence of beneficial effect from high-dose rifampin
Tuberculosis is usually treated with a 6-month rifampin-based regimen. Whether a strategy involving shorter initial treatment may lead to similar outcomes is unclear. In this adaptive, open-label, noninferiority trial, we randomly assigned participants with rifampin-susceptible pulmonary tuberculosis to undergo either standard treatment (rifampin and isoniazid for 24 weeks with pyrazinamide and ethambutol for the first 8 weeks) or a strategy involving initial treatment with an 8-week regimen, extended treatment for persistent clinical disease, monitoring after treatment, and retreatment for relapse. There were four strategy groups with different initial regimens; noninferiority was assessed in the two strategy groups with complete enrollment, which had initial regimens of high-dose rifampin-linezolid and bedaquiline-linezolid (each with isoniazid, pyrazinamide, and ethambutol). The primary outcome was a composite of death, ongoing treatment, or active disease at week 96. The noninferiority margin was 12 percentage points. Of the 674 participants in the intention-to-treat population, 4 (0.6%) withdrew consent or were lost to follow-up. A primary-outcome event occurred in 7 of the 181 participants (3.9%) in the standard-treatment group, as compared with 21 of the 184 participants (11.4%) in the strategy group with an initial rifampin-linezolid regimen (adjusted difference, 7.4 percentage points; 97.5% confidence interval [CI], 1.7 to 13.2; noninferiority not met) and 11 of the 189 participants (5.8%) in the strategy group with an initial bedaquiline-linezolid regimen (adjusted difference, 0.8 percentage points; 97.5% CI, -3.4 to 5.1; noninferiority met). The mean total duration of treatment was 180 days in the standard-treatment group, 106 days in the rifampin-linezolid strategy group, and 85 days in the bedaquiline-linezolid strategy group. The incidences of grade 3 or 4 adverse events and serious adverse events were similar in the three groups. A strategy involving
Tuberculosis (TB) is an ancient infectious disease. Before the availability of effective drug therapy, it had high morbidity and mortality. In the past 100 years, the discovery of revolutionary anti-TB drugs such as streptomycin, isoniazid, pyrazinamide, ethambutol and rifampicin, along with drug combination treatment, has greatly improved TB control globally. As anti-TB drugs were widely used, multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains of Mycobacterium tuberculosis emerged due to acquired genetic mutations, and this now presents a major problem for effective treatment. Genes associated with drug resistance have been identified, including katG mutations in isoniazid resistance, rpoB mutations in rifampin resistance, pncA mutations in pyrazinamide resistance, and gyrA mutations in quinolone resistance. The major mechanisms of drug resistance include loss of enzyme activity in prodrug activation, drug target alteration, overexpression of drug target, and overexpression of the efflux pump. During the disease process, Mycobacterium tuberculosis may reside in different microenvironments where it is expose to acidic pH, low oxygen, reactive oxygen species and anti-TB drugs, which can facilitate the development of non-replicating persisters and promote bacterial survival. The mechanisms of persister formation may include toxin-antitoxin (TA) modules, DNA protection and repair, protein degradation such as trans-translation, efflux, and altered metabolism. In recent years, the use of new anti-TB drugs, repurposed drugs, and their drug combinations has greatly improved treatment outcomes in patients with both drug-susceptible TB and MDR/XDR-TB. The importance of developing more effective drugs targeting persisters of Mycobacterium tuberculosis is emphasized. In addition, host-directed therapeutics using both conventional drugs and herbal medicines for more effective TB treatment should also be explored. In this article, we review historical aspects