The pharmacokinetics of alpelisib has been studied in healthy subjects and adult patients with solid tumors and are presented as mean (% CV) under fed conditions unless otherwise specified. Alpelisib maximum plasma concentration (Cmax) was 277 ng/mL (24%) and area under the curve (AUC) was 2,090 hr*ng/mL (24%) following administration of a single 50 mg dose of VIJOICE. Steady state alpelisib Cmax and AUC increased proportionally over the dose range of 30 mg (0.6 times the lowest approved recommended dosage) to 450 mg (1.8 times the highest approved recommended dosage) under fed conditions. The mean accumulation of alpelisib was 1.3 to 1.5 and steady state plasma concentrations were reached within 3 days following daily dosage.
Absorption
The median time to reach peak plasma concentration (Tmax) ranged between 2.0 to 4.0 hours.
Effect of Food
A high-fat high-calorie (HFHC) meal (985 calories with 58.1 g of fat) increased alpelisib AUC by 73% and Cmax by 84%, and a low-fat low-calorie (LFLC) meal (334 calories with 8.7 g of fat) increased alpelisib AUC by 77% and Cmax by 145% following administration of a single 300 mg dose of alpelisib as tablets. No clinically relevant differences in alpelisib AUC were observed between LFLC and HFHC meals.
No clinically relevant food effect on alpelisib pharmacokinetics was observed after a single 50 mg oral dose of VIJOICE as granules taken with a LFLC meal as compared to that taken under fasted conditions.
No clinically relevant differences in alpelisib Cmax and AUC were observed following administration of a single 50 mg dose of VIJOICE as granules or tablets taken with a LFLC meal.
Distribution
The apparent volume of distribution of alpelisib at steady state is 114 L (46%). Protein binding of alpelisib is 89% and is independent of concentration.
Elimination
The half-life of alpelisib is predicted to be 8 to 9 hours. The clearance of alpelisib is 9.2 L/hr (21%) under fed conditions.
Metabolism
Alpelisib is primarily metabolized by chemical and enzymatic hydrolysis to form its metabolite BZG791 and followed by CYP3A4 mediated hydroxylation.
Excretion
Following a single oral dose of 400 mg (1.6 times the highest approved recommended dosage) radiolabeled alpelisib under fasted condition, 81% of the administered dose was recovered in feces (36% unchanged) and 14% (2% unchanged) in urine. CYP3A4-mediated metabolites (12%) and glucuronides amounted to approximately 15% of the dose.
Specific Populations
No clinically significant differences in the pharmacokinetics of alpelisib were predicted based on age (21 to 87 years), sex, race/ethnicity (Japanese or Caucasian), body weight (37 to 181 kg), mild to moderate renal impairment (CLcr 30 to < 90 mL/min based on the Cockcroft-Gault formula), or mild to severe hepatic impairment (Child-Pugh Class A, B, and C). The effect of severe renal impairment (CLcr < 30 mL/min) on the pharmacokinetics of alpelisib is unknown.
Drug Interaction Studies
Clinical Studies and Model-Informed Approaches
Acid Reducing Agents: No clinically significant differences in the pharmacokinetics of alpelisib were observed when used concomitantly with ranitidine (H2 receptor antagonist) and administered with food as directed.
Concomitant use of ranitidine decreased alpelisib AUC approximately 30% and Cmax by 51% with a single 300 mg oral dose (1.2 times the highest approved recommended dosage) of alpelisib under the fasted state. In the presence of a low-fat low-calorie meal, AUC was decreased by 21% and Cmax by 36% with ranitidine.
CYP3A4, CYP2C8, CYP2C9, CYP2C19 and CYP2B6 Substrates: Coadministration of repeated doses of alpelisib 300 mg with a single-dose of sensitive substrates of CYP3A4 (midazolam), CYP2C8 (repaglinide), CYP2C9 (warfarin), CYP2C19 (omeprazole) and CYP2B6 (bupropion), administered as a cocktail did not show clinically significant pharmacokinetic interactions.
No clinically significant differences in pharmacokinetics of everolimus (a substrate of CYP3A4 and P-gp) were observed when used concurrently with alpelisib.
Effect of CYP3A4 Inducers on Alpelisib: Coadministration of repeat doses of rifampin (a strong CYP3A4 inducer) with a single 300 mg dose of alpelisib decreased alpelisib Cmax by 38% and AUC by 57%, respectively. Coadministration of rifampin with repeat doses of 300 mg alpelisib decreased alpelisib Cmax by 59% and AUC by 74%, respectively.
Model-Informed Approaches
Coadministration of repeat doses of ketoconazole (a strong CYP3A4 inhibitor) with a single 300 mg dose of alpelisib is expected to increase alpelisib AUC by 37% or less.
Coadministration of repeat doses of efavirenz (a moderate CYP3A4 inducer) with a single 300 mg dose of alpelisib is expected to decrease alpelisib AUC by 30% or less.
In Vitro Studies
Effect of Transporter on Alpelisib: Alpelisib is a substrate of BCRP.
Effect of Alpelisib on Transporters: Alpelisib is an inhibitor of P-gp. Alpelisib has a low potential to inhibit BCRP, MRP2, BSEP, OATP1B1, OATP1B3, OCT1, OAT1, OAT3, OCT2, MATE1, and MATE2K at clinically relevant concentrations.