Suzetrigine

JOURNAVX is indicated for the treatment of moderate to severe acute pain, including postoperative pain, in adults. JOURNAVX is a sodium channel blocker indicated for the treatment of moderate to severe acute pain, including postoperative pain, in adults. ( 1 )

Tablets: 50 mg, blue, film-coated, oblong tablets debossed with "VX50" on one side and plain on the other. Tablets: 50 mg ( 3 )

Concomitant use of JOURNAVX with strong CYP3A inhibitors is contraindicated [see Warnings and Precautions (5.1) , Drug Interactions (7.1) ] . Concomitant use with strong CYP3A inhibitors is contraindicated. ( 4 )

Moderate and Severe Hepatic Impairment : Avoid use in patients with severe hepatic impairment (Child-Pugh Class C). Use in patients with moderate hepatic impairment may increase the risk of adverse reactions. The recommended dosage is lower in patients with moderate hepatic impairment (Child-Pugh Class B) than those with normal hepatic function. ( 5.4 )

5.1 Increased Risk of Adverse Reactions with Concomitant Use with Strong or Moderate CYP3A Inhibitors Strong and moderate CYP3A inhibitors increase suzetrigine and M6-SUZ (active metabolite) exposures which may cause JOURNAVX adverse reactions. Concomitant use of JOURNAVX with strong CYP3A inhibitors is contraindicated [see Drug Interactions (7.1) , Clinical Pharmacology (12.3) ] . Reduce the JOURNAVX dosage with moderate CYP3A inhibitors [see Dosage and Administration (2.3) ] .

5.2 Risk of Drug Interactions with Certain CYP3A Substrates Suzetrigine is an inducer of CYP3A. If JOURNAVX is used concomitantly with sensitive CYP3A substrates or CYP3A substrates where minimal concentration changes may lead to loss of efficacy, refer to the Prescribing Information for the CYP3A substrates for dosing instructions. Dosage adjustment of the concomitant CYP3A substrates may be required when initiating or discontinuing JOURNAVX [see Drug Interactions (7.2) , Clinical Pharmacology (12.3) ].

5.3 Risk of Drug Interactions with Certain Hormonal Contraceptives JOURNAVX-treated patients taking concomitant hormonal contraceptives containing progestins other than levonorgestrel and norethindrone should use additional nonhormonal contraceptives (such as condoms) or use alternative contraceptives (e.g., a combined oral contraceptive containing ethinyl estradiol as the estrogen and levonorgestrel or norethindrone as the progestin, an intrauterine system) during JOURNAVX treatment and for 28 days after discontinuation of JOURNAVX [see Drug Interactions (7.2) , Clinical Pharmacology (12.3) ].

5.4 Risk of Adverse Reactions in Patients with Moderate and Severe Hepatic Impairment Patients with moderate hepatic impairment have higher systemic exposures of suzetrigine and M6-SUZ (active metabolite) than those with normal hepatic function which may increase the risk of JOURNAVX related adverse reactions [see Use in Specific Populations (8.6) , Clinical Pharmacology (12.3) ] . Avoid use of JOURNAVX in patients with severe hepatic impairment (Child-Pugh Class C). The recommended JOURNAVX dosage is lower in patients with moderate hepatic impairment (Child-Pugh Class B) than those with normal hepatic function [see Dosage and Administration (2.2) ].

The most common adverse reactions (greater incidence in JOURNAVX-treated patients compared to placebo-treated patients) were pruritus, muscle spasms, increased creatine phosphokinase, and rash. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Vertex Pharmaceuticals Incorporated at 1-877-634-8789 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. The safety profile of JOURNAVX is primarily based on data from the pooled, double-blind, placebo- and active-controlled trials in 874 adult patients with moderate to severe acute pain following full abdominoplasty (Trial 1) and bunionectomy (Trial 2) [see Clinical Studies (14) ] , with supportive safety data from one single arm trial in 256 adult patients with moderate to severe acute pain in a broad range of acute pain conditions (Trial 3). In Trials 1 and 2, 874 patients received at least one dose of JOURNAVX. The proportion of patients in Trials 1 and 2 who discontinued study drug prematurely due to adverse events was: 0.6% in JOURNAVX-treated patients (postprocedural hematoma [0.2%], hypotension [0.2%], syncope [0.1%]), 0.6% in hydrocodone bitartrate/acetaminophen (HB/APAP)-treated patients (hypotension/orthostatic hypotension [0.2%], migraine [0.1%], intra-abdominal hematoma [0.1%], nausea [0.1%], pyrexia [0.1%]), and 0.2% in placebo-treated patients (hypotension [0.2%], tachycardia [0.2%]). The safety profile of JOURNAVX was also evaluated by the following subgroup analyses: age (≥ 18 to < 65 years and ≥ 65 years), sex, and race. Since most patients enrolled in the clinical trials were ≥ 18 to < 65 years of age, female, and white, there was insufficient data to detect differences in safety signals between these subgroups. Table 2 displays adverse reactions that occurred more frequently in JOURNAVX-treated patients than placebo-treated patients in the pooled Trials 1 and 2. Table 2: Adverse Reactions Reported in ≥1% of JOURNAVX-Treated Patients and Greater than Rate of Placebo in Two 48-hour Trials in Moderate to Severe Acute Pain (Trials 1 and 2, Pooled) Adverse Reactions (Preferred Term) Placebo (N = 438) n (%) JOURNAVX (N = 874) n (%) HB/APAP Patients received 5 mg/325 mg of oral hydrocodone bitartrate/acetaminophen (HB/APAP) every 6 hours. (N = 879) n (%) Pruritus 7 (1.6) 18 (2.1) 30 (3.4) Muscle spasms 2 (0.5) 11 (1.3) 6 (0.7) Increased blood creatine phosphokinase 2 (0.5) 10 (1.1) 7 (0.8) Rash 2 (0.5) 10 (1.1) 6 (0.7) Nausea and Vomiting In Trial 1, the incidence of patients who experienced either nausea or vomiting was 20% in JOURNAVX-treated patients, 33% in HB/APAP-treated patients, and 25% in placebo-treated patients. In Trial 2, the incidence of patients who experienced either nausea or vomiting was 9% in JOURNAVX-treated patients, 16% in HB/APAP-treated patients, and 12% in placebo-treated patients. Laboratory Abnormalities Creatine Phosphokinase Elevations: In Trials 1 and 2, 2.9% of JOURNAVX-treated patients and 1.2% of placebo-treated patients had a creatine phosphokinase (CPK) level > 3 times the upper limit of normal. The incidence of increased blood CPK was 1.1% in JOURNAVX-treated patients and 0.5% in placebo-treated patients. All reports of CPK elevations occurred in the post-surgical setting. There were no associated signs or symptoms, no serious adverse reactions, and no patients required treatment discontinuation or interruption. Decreased Estimated Glomerular Filtration Rate: In Trials 1 and 2, 2.5% of JOURNAVX-treated patients and 0.9% of placebo-treated patients had a decrease in estimated glomerular filtration rate (eGFR) of ≥ 25% but < 50%. Follow-up eGFR data for these controlled trials was not available after treatment discontinuation. Similar decreases in eGFR also occurred in Trial 3 (the open-label Phase 3 study) and appeared to resolve to baseline by the final safety follow-up visit. There was no control arm for comparison. There were no adverse reactions of eGFR decrease in JOURNAVX-treated patients. Adverse Reactions from the Open-Label Study (Trial 3) In an open-label study of patients with moderate to severe acute pain following a surgical procedure or nonsurgical condition [NCT05661734], a total of 256 adult patients received at least one dose of JOURNAVX. Patients received 100 mg as a first dose, then 50 mg every 12 hours and continued to receive JOURNAVX for up to 14 days or until their pain resolved. Rescue medication of 650 mg of acetaminophen and 400 mg of ibuprofen together every 6 hours was permitted as needed for pain relief. The patients' perceptions of pain control was captured by patient global assessment (PGA). The mean duration of treatment with JOURNAVX was 9.6 days. The majority of patients were female (68%), and the median age was 43 years (range: 18 to 78). In Trial 3, a total of 222 (87%) patients received JOURNAVX for post-surgical pain; orthopedic surgery was the most common (e.g., ligament operation, arthrodesis), followed by plastic surgery (e.g., liposuction, mammoplasty), otorhinolaryngologic surgery (e.g., nasal septal operation, turbinoplasty), and general and urologic surgery (e.g., inguinal hernia repair). Thirty-four (13%) patients received JOURNAVX for non-surgical pain (e.g., arthralgias, limb pain, and sprains/strains). The proportion of patients who discontinued study drug prematurely was 2% due to adverse events (arrhythmia [0.4%], nausea [0.4%], somnolence [0.4%], rash [0.4%]) and 1.6% due to lack of efficacy. The safety profile of JOURNAVX in Trial 3 was consistent with that observed in Trials 1 and 2.

Strong and Moderate CYP3A inhibitors : Concomitant use with strong CYP3A inhibitors is contraindicated. Reduce the JOURNAVX dose when used concomitantly with moderate CYP3A inhibitors. Avoid food or drink containing grapefruit. ( 2.3 , 7.1 , 12.3 ) Strong and Moderate CYP3A inducers : Avoid JOURNAVX use with strong or moderate CYP3A inducers. ( 7.1 , 12.3 ) CYP3A substrates : If JOURNAVX is used concomitantly with sensitive CYP3A substrates or CYP3A substrates where minimal concentration changes may lead to loss of efficacy, refer to the Prescribing Information for the CYP3A substrates for dosing instructions. Dosage modification of the concomitant CYP3A substrates may be required when initiating or discontinuing JOURNAVX. ( 7.2 , 12.3 ) Hormonal contraceptives : JOURNAVX-treated patients using hormonal contraceptives containing progestins other than levonorgestrel and norethindrone should use an additional nonhormonal contraceptive method or an alternative hormonal contraceptive during concomitant use and for 28 days after JOURNAVX discontinuation. ( 7.2 )

7.1 Effect of Other Drugs on JOURNAVX Table 3 describes drug interactions where concomitant use of another drug affects the use of JOURNAVX. Table 3: Drug Interactions: Concomitant Use of Other Drugs that Affect the Use of JOURNAVX Strong and Moderate Food or drink containing grapefruit should be avoided during treatment with JOURNAVX. CYP3A Inhibitors Prevention or Management Strong CYP3A inhibitors: Concomitant use of JOURNAVX with strong CYP3A inhibitors is contraindicated [see Warnings and Precautions (5.1) ] . Moderate CYP3A inhibitors: Reduce the JOURNAVX dosage [see Dosage and Administration (2.3) , Warnings and Precautions (5.1) ] . Mechanism and Clinical Effect(s) Suzetrigine and M6-SUZ are CYP3A substrates. Strong and moderate CYP3A inhibitors increase suzetrigine and M6-SUZ (active metabolite of suzetrigine) exposures [see Clinical Pharmacology (12.3) ], which may cause JOURNAVX adverse reactions . Strong and Moderate CYP3A Inducers Prevention or Management Avoid concomitant use of JOURNAVX with strong and moderate CYP3A inducers. Mechanism and Clinical Effect(s) Suzetrigine and M6-SUZ are CYP3A substrates. Concomitant use of strong or moderate CYP3A inducers results in reduced exposures of suzetrigine and M6-SUZ, which may result in reduced JOURNAVX efficacy [see Clinical Pharmacology (12.3) ] .

7.2 Effect of JOURNAVX on Other Drugs CYP3A Substrates If JOURNAVX is used concomitantly with sensitive CYP3A substrates or CYP3A substrates where minimal concentration changes may lead to loss of efficacy, refer to the Prescribing Information for the CYP3A substrates for dosing instructions. Dosage modification of the concomitant CYP3A substrates may be required when initiating or discontinuing JOURNAVX [see Warnings and Precautions (5.2) ] . Suzetrigine is an inducer of CYP3A. Concomitant use with JOURNAVX may reduce the exposure of sensitive CYP3A substrates which may decrease the efficacy of these substrates. Discontinuation of JOURNAVX may increase the exposure of sensitive CYP3A substrates [see Warnings and Precautions (5.2) , Clinical Pharmacology (12.3) ] . Hormonal Contraceptives JOURNAVX-treated patients using hormonal contraceptives containing progestins other than levonorgestrel and norethindrone should use additional nonhormonal contraceptives (such as condoms), or use alternative contraceptives (such as a combined oral contraceptive containing ethinyl estradiol as the estrogen and levonorgestrel or norethindrone as the progestin, or an intrauterine system) during treatment with JOURNAVX and for 28 days after discontinuation of JOURNAVX [see Warnings and Precautions (5.3) ] . JOURNAVX did not result in clinically significant changes in the pharmacokinetics of ethinyl estradiol and levonorgestrel when used concomitantly with an oral contraceptive containing ethinyl estradiol and levonorgestrel [see Clinical Pharmacology (12.3) ] .

8.1 Pregnancy Risk Summary There are no available data on the use of JOURNAVX during pregnancy to evaluate for a drug-associated risk of major birth defects, miscarriage or other adverse maternal or fetal outcomes. In animal reproduction studies in rats, effects on implantation and maintenance of pregnancy occurred at oral suzetrigine doses of ≥ 2.2-times the maximum recommended human dose (MRHD) when administered during early embryonic development or throughout organogenesis. In a pre- and postnatal development study, reduced mean gestation length and increased postnatal pup mortality were observed at maternal rat exposures of 1.6-times the MRHD and decreased rat pup body weights were observed during the period of birth to weaning at maternal exposures of 2.2-times the MRHD. No malformations were observed when suzetrigine was administered orally to rats and rabbits during the period of organogenesis at doses up to 2.2- and 5.9-times, respectively, the MRHD. The clinical relevance of these findings is unclear. The background risk of major birth defects and miscarriage in patients with moderate to severe acute pain is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Data Animal Data Suzetrigine was administered orally to pregnant rabbits during the period of organogenesis at 50, 100, and 200 mg/kg/day (approximately 1.6-, 3.1-, and 5.9-times, respectively, the steady state MRHD exposure based on AUC). Increased post-implantation loss and lower fetal body weight were observed at 200 mg/kg/day, which is a dose that also caused maternal toxicity. No adverse embryofetal effects were observed at doses up to 100 mg/kg. Suzetrigine was administered orally to pregnant rats during the period of organogenesis at 5, 10, and 15 mg/kg/day (approximately 0.57-, 1.6-, and 2.2-times, respectively, the steady state MRHD exposure based on AUC). Increased post-implantation loss and lower number of live fetuses were observed at 15 mg/kg/day. No adverse embryofetal effects were observed at doses up to 10 mg/kg. Placental transfer of suzetrigine was observed in pregnant rats. In a pre- and postnatal development study, suzetrigine was administered orally to pregnant rats at doses of 5, 10, and 15 mg/kg/day (approximately 0.57-, 1.6-, and 2.2-times, respectively, the steady state MRHD exposure based on AUC) from Gestation Day 6 through Lactation Day 20. Reduced mean gestation length and increased postnatal pup mortality between birth and Postnatal Day 4 were observed at ≥ 10 mg/kg and increased incidences of fully resorbed litters, lower live newborn pups, and reductions in pup body weights were observed at 15 mg/kg. No effects on learning and memory or sexual maturation were observed at dose up to 15 mg/kg/day. The effects on implantation, maintenance of pregnancy, reduced mean gestation length, and increased postnatal pup mortality in rats are of uncertain relevance to humans.

8.2 Lactation Risk Summary There are no data on the presence of suzetrigine or its metabolites in human milk, the effects on the breastfed infant, or the effects on milk production. Suzetrigine is present in animal milk. When a drug is present in animal milk, it is likely that the drug will be present in human milk. The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for JOURNAVX and any potential adverse effects on the breastfed child from JOURNAVX or from the underlying maternal condition.

8.3 Females and Males of Reproductive Potential Contraception Advise patients using hormonal contraceptives containing progestins other than levonorgestrel and norethindrone to use an additional nonhormonal contraceptive or to use alternative contraceptives during JOURNAVX treatment and for 28 days after discontinuation of JOURNAVX [see Drug Interactions (7.2) ]. Infertility In a female fertility study in rats, increased pre-implantation loss was observed at oral suzetrigine doses of ≥ 2.2-times the MRHD when administered prior to mating and through Gestation Day 7. Following discontinuation of suzetrigine for 4 weeks, the increased pre-implantation loss in rats was not observed. The finding in rats may be explained by the effect of suzetrigine on the rat progesterone receptor, which was more sensitive to suzetrigine than the human progesterone receptor based on in vitro studies. The finding in the rat study is of uncertain relevance to humans. JOURNAVX may reversibly impact the likelihood of females of reproductive potential to become pregnant while on treatment. Patients using contraceptives should continue to use contraceptives [see Nonclinical Toxicology (13.1) ].

8.4 Pediatric Use The safety and effectiveness of JOURNAVX has not been established in pediatric patients.

8.5 Geriatric Use Of the total 1130 patients with moderate to severe acute pain who received JOURNAVX in the Phase 3 studies [see Clinical Studies (14) ] , 71 patients (6.3%) were 65 years of age and older. Clinical studies of JOURNAVX did not include sufficient numbers of patients aged 65 years and older to determine whether they respond differently from younger patients. However, based on population pharmacokinetic analyses in patients with ages ranging from 18 to 75 years, age does not have a clinically relevant impact on suzetrigine exposure [see Clinical Pharmacology (12.3) ] .

8.6 Hepatic Impairment JOURNAVX has not been studied in patients with severe hepatic impairment. Avoid use of JOURNAVX in patients with severe hepatic impairment (Child-Pugh Class C) [see Warnings and Precautions (5.4) ]. The recommended JOURNAVX dosage is lower in patients with moderate hepatic impairment (Child-Pugh Class B) [see Dosage and Administration (2.2) ] than those with normal hepatic function. The recommended dosage in patients with mild hepatic impairment (Child-Pugh Class A) is the same as those with normal hepatic function. Patients with moderate hepatic impairment had greater suzetrigine and M6-SUZ (the active metabolite) exposure than those with normal hepatic function [see Clinical Pharmacology (12.3) ] , which may increase the risk of suzetrigine adverse reactions.

8.7 Renal Impairment JOURNAVX has not been studied in patients with renal impairment of eGFR < 15 mL/min. Avoid use of JOURNAVX in patients with renal impairment of eGFR < 15 mL/min [see Clinical Pharmacology (12.3) ] . The recommended dosage in patients with eGFR > 15 mL/min is the same as those with normal kidney function.

Suzetrigine is a selective blocker of the Na V 1.8 voltage-gated sodium channel, compared to other known voltage-gated sodium channels (Na V 1.1 through 1.9). Na V 1.8 is expressed in peripheral sensory neurons including dorsal root ganglion neurons, where its role is to transmit pain signals (action potentials). By selectively inhibiting Na V 1.8 channels, suzetrigine inhibits transmission of pain signals to the spinal cord and brain. M6-SUZ, a major active metabolite, is a less potent inhibitor of Na V 1.8 than suzetrigine by 3.7-fold.