PRETOMANID Drug Interactions: What You Need to Know

INTERACTIONS

• Strong or moderate CYP3A4 inducers such as rifampin or efavirenz: Avoid co-administration. ( 5.6 , 7.1 )
• Organic anion transporter-3 (OAT3) substrates: Monitor for OAT3 substrate drug-related adverse reactions and consider dosage reduction for OAT3 substrate drugs, if needed. ( 7.2 )

7.1 Effect of Other Drugs on Pretomanid CYP3A4 Inducers Co-administration of pretomanid with rifampin and efavirenz resulted in a decrease in pretomanid plasma concentrations <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.3) ]</span> . Avoid co-administration of the combination regimen of Pretomanid Tablets, bedaquiline, and linezolid with rifampin, efavirenz, or other strong or moderate CYP3A4 inducers. Refer to the prescribing information for bedaquiline for additional information about drug interactions with CYP3A4. Lopinavir/Ritonavir Co-administration of pretomanid with lopinavir/ritonavir did not affect the plasma concentrations of pretomanid <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.3) ]</span> . Lopinavir/ritonavir can be co-administered with the combination regimen of Pretomanid Tablets, bedaquiline, and linezolid.

7.2 Effect of Pretomanid on Other Drugs Midazolam Co-administration of pretomanid with the CYP3A4 substrate, midazolam, resulted in no clinically significant effect on the pharmacokinetics of midazolam or its major metabolite, 1-hydroxy-midazolam <span class="opacity-50 text-xs">[see Clinical Pharmacology (12.3) ]</span> . The combination regimen of Pretomanid Tablets, bedaquiline, and linezolid can be administered with CYP3A4 substrate drugs.

Organic Anion

Transporter-3 (OAT3), BCRP, OATP1B3 and P-gp Substrates The effect of co-administration of pretomanid on the pharmacokinetics of OAT3 substrates in humans is unknown. However, in vitro studies indicate that pretomanid significantly inhibits the OAT3 drug transporter [see Clinical Pharmacology (12.3) ] , which could result in increased concentrations of OAT3 substrate drugs clinically and may increase the risk of adverse reactions associated with these drugs. If pretomanid is co-administered with OAT3 substrate drugs (e.g., methotrexate, indomethacin, ciprofloxacin), increase monitoring for OAT3 substrate drug-related adverse reactions and consider dosage reduction for OAT3 substrate drugs, if needed. Refer to the prescribing information of the co-administered drug for dosage reduction information. In vitro studies cannot exclude the possibility that pretomanid is an inhibitor of BCRP, OATP1B3 and P-gp [see Clinical Pharmacology (12.3) ] . No clinical studies have been performed to investigate these interactions. Therefore, it cannot be excluded that co-administration of pretomanid with sensitive OATP1B3 substrates (e.g., valsartan, statins), BCRP substrates (e.g., rosuvastatin, prazosin, glyburide, sulfasalazine) and P-gp substrates (e.g., digoxin, dabigatran etexilate, verapamil) may increase their exposure. If pretomanid is co-administered with substrates of OATP1B3, BCRP, or P-gp, increased monitoring for drug-related adverse reactions to the co-administered medicinal product should be performed.

Pretomanid Tablets used in the combination regimen with bedaquiline and linezolid are contraindicated in patients for whom bedaquiline and/or linezolid are contraindicated. Refer to the bedaquiline and linezolid prescribing information.

• Pretomanid Tablets used in combination with bedaquiline and linezolid are contraindicated in patients for whom bedaquiline and/or linezolid is contraindicated. ( 4 )

AND PRECAUTIONS

• Hepatic adverse reactions were reported with the use of the combination regimen of Pretomanid Tablets, bedaquiline, and linezolid. Monitor symptoms and signs and liver‑related laboratory tests. Interrupt treatment with the entire regimen if evidence of liver injury occurs. ( 5.2 )
• Myelosuppression was reported with the use of the combination regimen of Pretomanid Tablets, bedaquiline, and linezolid. Monitor complete blood counts. Decrease or interrupt linezolid dosing if significant myelosuppression develops or worsens. ( 5.3 )
• Peripheral and optic neuropathy were reported with the use of the combination regimen of Pretomanid Tablets, bedaquiline, and linezolid. Monitor visual function. Obtain an ophthalmologic evaluation if there are symptoms of visual impairment. Decrease or interrupt linezolid dosing if neuropathy develops or worsens. ( 5.4 )
• QT prolongation was reported with the use of the combination regimen of Pretomanid Tablets, bedaquiline, and linezolid. Use with drugs that prolong the QT interval may cause additive QT prolongation. Monitor ECGs. Discontinue the combination regimen of Pretomanid Tablets, bedaquiline, and linezolid if significant ventricular arrhythmia or if QTcF interval prolongation of greater than 500 ms develops. ( 5.5 )
• Reproductive effects: Pretomanid caused testicular atrophy and impaired fertility in male rats. Advise patients of reproductive toxicities seen in animal studies and that the potential effects on human male fertility have not been adequately evaluated. ( 5.7 , 13.1 )
• Lactic acidosis was reported with the use of the combination regimen of Pretomanid Tablets, bedaquiline, and linezolid. Consider interrupting linezolid or the entire combination regimen of Pretomanid Tablets, bedaquiline, and linezolid dosing if significant lactic acidosis develops. ( 5.8 )

5.1 Risks Associated with the Combination Treatment Regimen Pretomanid Tablet is indicated for use as part of a regimen in combination with bedaquiline and linezolid. Refer to the prescribing information for bedaquiline and linezolid for additional risk information. Warnings and Precautions related to bedaquiline and linezolid also apply to their use in the combination regimen with Pretomanid Tablets.

5.2 Hepatotoxicity Hepatic adverse reactions were reported with the combination regimen of Pretomanid Tablets, bedaquiline, and linezolid <span class="opacity-50 text-xs">[see Warnings and Precautions (5.1) , and Adverse Reactions (6.1) ]</span> . Avoid alcohol and hepatotoxic agents, including herbal supplements and drugs other than bedaquiline and linezolid <span class="opacity-50 text-xs">[see Indications and Usage (1) ]</span> while on Pretomanid Tablets, especially in patients with impaired hepatic function. Monitor symptoms and signs (such as fatigue, anorexia, nausea, jaundice, dark urine, liver tenderness, and hepatomegaly) and laboratory tests (ALT, AST, alkaline phosphatase, and bilirubin) at a minimum at baseline, at two weeks, and then monthly while on treatment and as needed. If evidence of new or worsening liver dysfunction occurs, test for viral hepatitides and discontinue other hepatotoxic medications. Interrupt treatment with the entire regimen if:

• Aminotransferase elevations are accompanied by total bilirubin elevation greater than 2 times the upper limit of normal.
• Aminotransferase elevations are greater than 8 times the upper limit of normal.
• Aminotransferase elevations are greater than 5 times the upper limit of normal and persist beyond 2 weeks.

5.3 Myelosuppression Myelosuppression (including anemia, leukopenia, thrombocytopenia, and pancytopenia) was reported with the combination regimen of Pretomanid Tablets, bedaquiline, and linezolid. Myelosuppression is a known adverse reaction of linezolid. Anemia can be life threatening <span class="opacity-50 text-xs">[see Warnings and Precautions (5.1) , and Adverse Reactions (6.1) ]</span> . When linezolid dosing, as part of the combination regimen of Pretomanid Tablets, bedaquiline, and linezolid, was reduced, interrupted, or discontinued, the observed hematologic abnormalities were reversible. Complete blood counts should be monitored at a minimum at baseline, at two weeks, and then monthly in patients receiving linezolid as part of the combination regimen of Pretomanid Tablets, bedaquiline, and linezolid. Decreasing linezolid to half the initial dose or interrupting linezolid dosing should be considered in patients who develop or have worsening myelosuppression <span class="opacity-50 text-xs">[see Dosage and Administration (2.2) ]</span> .

5.4 Peripheral and Optic Neuropathy Peripheral neuropathy and optic neuropathy were reported with the combination regimen of Pretomanid Tablets, bedaquiline, and linezolid <span class="opacity-50 text-xs">[see Warnings and Precautions (5.1) , and Adverse Reactions (6.1) ]</span> . Neuropathy is a known adverse reaction of long-term linezolid use. Neuropathy associated with linezolid is generally reversible or improved with appropriate monitoring and interruption, dose reduction, or discontinuation of linezolid dosing. When improvement in the peripheral neuropathy is observed, consider resuming linezolid at half the initial dose <span class="opacity-50 text-xs">[see Dosage and Administration (2.2) ]</span> . Monitor visual function in all patients receiving the combination regimen of Pretomanid Tablets, bedaquiline, and linezolid; if a patient experiences symptoms of visual impairment, interrupt linezolid dosing and obtain prompt ophthalmologic evaluation.

5.5 QT Prolongation QT prolongation was reported with the combination regimen of Pretomanid Tablets, bedaquiline, and linezolid <span class="opacity-50 text-xs">[see Warnings and Precautions (5.1) , Adverse Reactions (6.1) , and Clinical Pharmacology (12.2) ]</span> . QT prolongation is a known adverse reaction of bedaquiline. Obtain an ECG before initiation of treatment, and at least 2, 12, and 24 weeks after starting treatment with the combination regimen of Pretomanid Tablets, bedaquiline, and linezolid. Obtain serum potassium, calcium, and magnesium at baseline and correct if abnormal. Monitor these electrolytes if QT prolongation is detected <span class="opacity-50 text-xs">[see Adverse Reactions (6.1) ]</span> . The following may increase the risk for QT prolongation when patients are receiving bedaquiline as part of the combination regimen of Pretomanid Tablets, bedaquiline, and linezolid: a history of Torsade de Pointes, congenital long QT syndrome, ongoing hypothyroidism, ongoing bradyarrhythmia, uncompensated heart failure, or serum calcium, magnesium, or potassium levels below the lower limits of normal. If necessary, bedaquiline treatment initiation could be considered in these patients after a favorable benefit-risk assessment and with frequent ECG monitoring. Discontinue the combination regimen of Pretomanid Tablets, bedaquiline, and linezolid if the patient develops clinically significant ventricular arrhythmia or a QTcF interval of greater than 500 ms (confirmed by repeat ECG). If syncope occurs, obtain an ECG to detect QT prolongation.

5.6 Drug Interactions CYP3A4 Inducers Pretomanid may be in part metabolized by CYP3A4 <span class="opacity-50 text-xs">[see Drug Interactions (7.1) and Clinical Pharmacology (12.3) ]</span>. Avoid co‑administration of strong or moderate CYP3A4 inducers, such as rifampin or efavirenz, during treatment with pretomanid.

5.7 Reproductive Effects Pretomanid caused testicular atrophy and impaired fertility in male rats. Advise patients of reproductive toxicities seen in animal studies and that the potential effects on human male fertility have not been adequately evaluated <span class="opacity-50 text-xs">[see Use in Specific Populations (8.3) and Nonclinical Toxicology (13.1) ]</span> .

5.8 Lactic Acidosis Lactic acidosis was reported with the combination regimen of Pretomanid Tablets, bedaquiline, and linezolid <span class="opacity-50 text-xs">[see Warnings and Precautions (5.1) and Adverse Reactions (6.1) ]</span> . Lactic acidosis is a known adverse reaction of linezolid. Patients who develop recurrent nausea or vomiting should receive immediate medical evaluation, including evaluation of bicarbonate and lactic acid levels, and interruption of linezolid or the entire combination regimen of Pretomanid Tablets, bedaquiline, and linezolid should be considered.