Dosing & Uses
Dosage Forms & Strengths
capsule
- 25mg
- 100mg
oral solution
- 20mg/mL
Solid Tumors
Indicated for adults and pediatric patients with solid tumors that have a neurotrophic tyrosine receptor kinase (NTRK) gene fusion without a known acquired resistance mutation, are metastatic or where surgical resection is likely to result in severe morbidity, and have no alternative treatments or have progressed following treatment
100 mg PO BID
Continue until disease progression or until unacceptable toxicity
Dosage Modifications
Dosage modifications for adverse reactions
-
Body Surface Area (BSA) ≥1 m2
- First occurrence: 75 mg BID
- Second occurrence: 50 mg BID
- Third occurrence: 100 mg qDay
- Unable to tolerate 100 mg qDay: Permanently discontinue
Grade ≥3 adverse reactions
- Withhold until reaction resolves or improves to baseline or Grade ≤1
- Resolved within 4 weeks: Resume at next dosage modification
- Unresolved within 4 weeks: Permanently discontinue
Strong CYP3A4 inhibitors
- Avoid coadministration
- If unavoidable, reduce larotrectinib dose by 50%
- Once strong CYP3A4 inhibitor is discontinued for 3-5 elimination half-lives, resume larotrectinib at dose taken before initiating CYP3A4 inhibitor
Strong CYP3A4 inducers
- Avoid coadministration
- If unavoidable, double larotrectinib dose
- Once strong CYP3A4 inducer is discontinued for 3-5 elimination half-lives, resume larotrectinib at dose taken prior to initiating CYP3A4 inducer
Hepatic impairment
- Mild (Child-Pugh A): No dosage adjustment necessary
- Moderate to severe (Child-Pugh B or C): Reduce starting dose by 50%
Renal impairment
- Mild to severe: No dosage adjustment necessary
Dosing Considerations
Verify pregnancy status in females of reproductive potential before initiation
Patient selection
- Select patients based on presence of a NTRK gene fusion in tumor specimens
- Information on FDA-approved tests is available at http://www.fda.gov/companiondiagnostics
Dosage Forms & Strengths
capsule
- 25mg
- 100mg
oral solution
- 20mg/mL
Solid Tumors
ndicated for adults and pediatric patients with solid tumors that have a neurotrophic tyrosine receptor kinase (NTRK) gene fusion without a known acquired resistance mutation, are metastatic or where surgical resection is likely to result in severe morbidity, and have no alternative treatments or have progressed following treatment
Body surface area (BSA) <1 m2: 100 mg/m2 PO BID
BSA ≥1 m2: 100 mg PO BID
Continue until disease progression or until unacceptable toxicity
Dosage Modifications
Dosage modifications for adverse reactions
-
BSA <1 m2
- First occurrence: 75 mg/m2 BID
- Second occurrence: 50 mg/m2 BID
- Third occurrence: Not to exceed 25 mg/m2 BID; remain on 25 mg/m2 BID even if BSA becomes >1 m2 during treatment
- Unable to tolerate 25 mg/m2 BID: Permanently discontinue
BSA ≥1 m2
- First occurrence: 75 mg BID
- Second occurrence: 50 mg BID
- Third occurrence: 100 mg qDay
- Unable to tolerate 100 mg qDay: Permanently discontinue
Grade ≥3 adverse reactions
- Withhold until reaction resolves or improves to baseline or Grade ≤1
- Resolved within 4 weeks: Resume at next dosage modificatio
- Unresolved within 4 weeks: Permanently discontinue
Strong CYP3A4 inhibitors
- Avoid coadministration
- If unavoidable, reduce larotrectinib dose by 50%
- Once strong CYP3A4 inhibitor is discontinued for 3-5 elimination half-lives, resume larotrectinib at dose taken before initiating CYP3A4 inhibitor
Strong CYP3A4 inducers
- Avoid coadministration
- If unavoidable, double larotrectinib dose
- Once strong CYP3A4 inducer is discontinued for 3-5 elimination half-lives, resume larotrectinib at dose taken before initiating CYP3A4 inducer
Hepatic impairment
- Mild (Child-Pugh A): No dosage adjustment necessary
- Moderate to severe (Child-Pugh B or C): Reduce starting dose by 50%
Renal impairment
- Mild to severe: No dosage adjustment necessary
Dosing Considerations
Verify pregnancy status in females of reproductive potential before initiation
Patient selection
- Select patients based on presence of a NTRK gene fusion in tumor specimens
- Information on FDA-approved tests is available at http://www.fda.gov/companiondiagnostics
Interactions
Interaction Checker
No Results
Contraindicated
Serious - Use Alternative
Significant - Monitor Closely
Minor
Contraindicated (1)
- lonafarnib
larotrectinib will increase the level or effect of lonafarnib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated. Lonafarnib is a sensitive CYP3A4 substrate. Coadministration with strong or moderate CYP3A4 inhibitors is contraindicated.
Serious - Use Alternative (67)
- abametapir
abametapir will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. For 2 weeks after abametapir application, avoid taking drugs that are CYP3A4 substrates. If not feasible, avoid use of abametapir.
- amobarbital
amobarbital will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives.
- apalutamide
apalutamide will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives.
- atazanavir
atazanavir will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inhibitors is unavoidable, reduce larotrectinib dose by 50%. Resume prior larotrectinib dose once CYP3A4 inhibitor discontinued for 3-5 half-lives.
- avapritinib
larotrectinib will increase the level or effect of avapritinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of avapritinib with moderate CYP3A4 inhibitors. If unable to avoid, reduce avapritinib starting dose. See drug monograph Dosage Modifications.
- bosentan
bosentan will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives.
- butabarbital
butabarbital will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives.
- butalbital
butalbital will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives.
- carbamazepine
carbamazepine will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives
- chloramphenicol
chloramphenicol will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inhibitors is unavoidable, reduce larotrectinib dose by 50%. Resume prior larotrectinib dose once CYP3A4 inhibitor discontinued for 3-5 half-lives.
- clarithromycin
clarithromycin will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inhibitors is unavoidable, reduce larotrectinib dose by 50%. Resume prior larotrectinib dose once CYP3A4 inhibitor discontinued for 3-5 half-lives.
- cobicistat
cobicistat will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inhibitors is unavoidable, reduce larotrectinib dose by 50%. Resume prior larotrectinib dose once CYP3A4 inhibitor discontinued for 3-5 half-lives.
- conivaptan
conivaptan will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inhibitors is unavoidable, reduce larotrectinib dose by 50%. Resume prior larotrectinib dose once CYP3A4 inhibitor discontinued for 3-5 half-lives.
- dabrafenib
dabrafenib will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives
- darunavir
darunavir will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inhibitors is unavoidable, reduce larotrectinib dose by 50%. Resume prior larotrectinib dose once CYP3A4 inhibitor discontinued for 3-5 half-lives.
- efavirenz
efavirenz will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives
- entrectinib
larotrectinib will increase the level or effect of entrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of moderate CYP3A4 inhibitors with entrectinib, a CYP3A4 substrate. If coadministration unavoidable, reduce dose to 200 mg/day for patients aged 12 y or older with BSA >1.50m2. Resume previous entrectinib dose after discontinuing moderate CYP3A inhibitor for 3-5 elimination half-lives.
- enzalutamide
enzalutamide will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives
- erdafitinib
erdafitinib will increase the level or effect of larotrectinib by P-glycoprotein (MDR1) efflux transporter. Avoid or Use Alternate Drug. If coadministration unavoidable, separate administration by at least 6 hr before or after administration of P-gp substrates with narrow therapeutic index.
- etravirine
etravirine will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives
- fedratinib
larotrectinib will increase the level or effect of fedratinib by Other (see comment). Avoid or Use Alternate Drug. Avoid coadministration of fedratinib (a CYP3A4 and CYP2C19 substrate) with dual CYP3A4 and CYP2C19 inhibitor. Effect of coadministration of a dual CYP3A4 and CYP2C19 inhibitor with fedratinib has not been studied.
- fexinidazole
fexinidazole will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Fexinidazole inhibits CYP3A4. Coadministration may increase risk for adverse effects of CYP3A4 substrates.
- fosphenytoin
fosphenytoin will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives
- grapefruit
grapefruit will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inhibitors is unavoidable, reduce larotrectinib dose by 50%. Resume prior larotrectinib dose once CYP3A4 inhibitor discontinued for 3-5 half-lives.
- idelalisib
idelalisib will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inhibitors is unavoidable, reduce larotrectinib dose by 50%. Resume prior larotrectinib dose once CYP3A4 inhibitor discontinued for 3-5 half-lives.
- indinavir
indinavir will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inhibitors is unavoidable, reduce larotrectinib dose by 50%. Resume prior larotrectinib dose once CYP3A4 inhibitor discontinued for 3-5 half-lives.
- infigratinib
larotrectinib will increase the level or effect of infigratinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.
- itraconazole
itraconazole will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inhibitors is unavoidable, reduce larotrectinib dose by 50%. Resume prior larotrectinib dose once CYP3A4 inhibitor discontinued for 3-5 half-lives.
- ivosidenib
ivosidenib will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives
- ketoconazole
ketoconazole will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inhibitors is unavoidable, reduce larotrectinib dose by 50%. Resume prior larotrectinib dose once CYP3A4 inhibitor discontinued for 3-5 half-lives.
- lemborexant
larotrectinib will increase the level or effect of lemborexant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of lemborexant with moderate or strong CYP3A inhibitors.
- lopinavir
lopinavir will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inhibitors is unavoidable, reduce larotrectinib dose by 50%. Resume prior larotrectinib dose once CYP3A4 inhibitor discontinued for 3-5 half-lives.
- lorlatinib
lorlatinib will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives
- lumacaftor/ivacaftor
lumacaftor/ivacaftor will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives
- lurbinectedin
larotrectinib will increase the level or effect of lurbinectedin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.
- midazolam intranasal
larotrectinib will increase the level or effect of midazolam intranasal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration of moderate CYP3A4 inhibitors with midazolam intranasal causes higher midazolam systemic exposure, which may prolong sedation.
- mifepristone
mifepristone will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inhibitors is unavoidable, reduce larotrectinib dose by 50%. Resume prior larotrectinib dose once CYP3A4 inhibitor discontinued for 3-5 half-lives.
- mitotane
mitotane will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives
- mobocertinib
larotrectinib will increase the level or effect of mobocertinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If use of moderate CYP3A4 inhibitor unavoidable, reduce mobocertinib dose by ~50% (eg, 160 to 80 mg); closely monitor QTc interval.
- nafcillin
nafcillin will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives
- nefazodone
nefazodone will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inhibitors is unavoidable, reduce larotrectinib dose by 50%. Resume prior larotrectinib dose once CYP3A4 inhibitor discontinued for 3-5 half-lives.
- nelfinavir
nelfinavir will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inhibitors is unavoidable, reduce larotrectinib dose by 50%. Resume prior larotrectinib dose once CYP3A4 inhibitor discontinued for 3-5 half-lives.
- pemigatinib
larotrectinib will increase the level or effect of pemigatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration with strong or moderate CYP3A4 inhibitors is unavoidable, reduce pemigatinib dose (refer to drug monograph dosage modifications). After discontinuing the CYP3A4 inhibitor for 3 elimination half-lives, may resume previous pemigatinib dose.
- pentobarbital
pentobarbital will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives
- pexidartinib
larotrectinib will increase the level or effect of pexidartinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration with strong or moderate CYP3A4 inhibitors is unavoidable, reduce pexidartinib dose (refer to drug monograph dosage modifications). After discontinuing the CYP3A4 inhibitor for 3 elimination half-lives, may resume previous pexidartinib dose.
- phenobarbital
phenobarbital will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives
- phenytoin
phenytoin will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives
- posaconazole
posaconazole will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inhibitors is unavoidable, reduce larotrectinib dose by 50%. Resume prior larotrectinib dose once CYP3A4 inhibitor discontinued for 3-5 half-lives.
- primidone
primidone will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives
- ribociclib
ribociclib will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.
- rifabutin
rifabutin will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives
- rifampin
rifampin will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives
- rifapentine
rifapentine will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives
- ritonavir
ritonavir will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inhibitors is unavoidable, reduce larotrectinib dose by 50%. Resume prior larotrectinib dose once CYP3A4 inhibitor discontinued for 3-5 half-lives.
- saquinavir
saquinavir will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inhibitors is unavoidable, reduce larotrectinib dose by 50%. Resume prior larotrectinib dose once CYP3A4 inhibitor discontinued for 3-5 half-lives.
- secobarbital
secobarbital will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives
- selumetinib
larotrectinib will increase the level or effect of selumetinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration with strong or moderate CYP3A4 inhibitors cannot be avoided, reduce selumetinib dosage (refer to selumetinib monograph for further information). After discontinuation of the strong or moderate CYP3A4 inhibitor for 3 elimination half-lives, resume selumetinib dose that was taken before initiating the inhibitor.
- siponimod
larotrectinib will increase the level or effect of siponimod by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration of siponimod with a moderate or strong CYP3A4 inhibitor PLUS a moderate or strong CYP2C9 inhibitor is not recommended.
- sotorasib
sotorasib will decrease the level or effect of larotrectinib by P-glycoprotein (MDR1) efflux transporter. Avoid or Use Alternate Drug. If use is unavoidable, refer to the prescribing information of the P-gp substrate for dosage modifications.
- St John's Wort
St John's Wort will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inducers is unavoidable, double larotrectinib dose. Resume prior larotrectinib dose once CYP3A4 inducer discontinued for 3-5 half-lives
- stiripentol
stiripentol will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inhibitors is unavoidable, reduce larotrectinib dose by 50%. Resume prior larotrectinib dose once CYP3A4 inhibitor discontinued for 3-5 half-lives.
- tazemetostat
larotrectinib will increase the level or effect of tazemetostat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of tazemetostat with moderate CYP3A4 inhibitors. If coadministration is unavoidable, reduce tazemetostat current dose (see drug monograph Dosage Modifications).
- tepotinib
tepotinib will increase the level or effect of larotrectinib by P-glycoprotein (MDR1) efflux transporter. Avoid or Use Alternate Drug. If concomitant use unavoidable, reduce the P-gp substrate dosage if recommended in its approved product labeling.
- tipranavir
tipranavir will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inhibitors is unavoidable, reduce larotrectinib dose by 50%. Resume prior larotrectinib dose once CYP3A4 inhibitor discontinued for 3-5 half-lives.
- tucatinib
tucatinib will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid concomitant use of tucatinib with CYP3A substrates, where minimal concentration changes may lead to serious or life-threatening toxicities. If unavoidable, reduce CYP3A substrate dose according to product labeling.
- voriconazole
voriconazole will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of larotrectinib with strong CYP3A4 inhibitors is unavoidable, reduce larotrectinib dose by 50%. Resume prior larotrectinib dose once CYP3A4 inhibitor discontinued for 3-5 half-lives.
- voxelotor
voxelotor will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Voxelotor increases systemic exposure of sensitive CYP3A4 substrates. Avoid coadministration with sensitive CYP3A4 substrates with a narrow therapeutic index. Consider dose reduction of the sensitive CYP3A4 substrate(s) if unable to avoid.
Monitor Closely (20)
- atogepant
larotrectinib will increase the level or effect of atogepant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- berotralstat
berotralstat will increase the level or effect of larotrectinib by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor. Monitor or titrate P-gp substrate dose if coadministered.
- cenobamate
cenobamate will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Increase dose of CYP3A4 substrate, as needed, when coadministered with cenobamate.
- diazepam intranasal
larotrectinib will increase the level or effect of diazepam intranasal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Strong or moderate CYP3A4 inhibitors may decrease rate of diazepam elimination, thereby increasing adverse reactions to diazepam.
- elagolix
elagolix decreases levels of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.
- fedratinib
fedratinib will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Adjust dose of drugs that are CYP3A4 substrates as necessary.
- finerenone
larotrectinib will increase the level or effect of finerenone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Monitor serum potassium during initiation and dosage adjustment of either finererone or moderate CYP3A4 inhibitors. Adjust finererone dosage as needed.
- isavuconazonium sulfate
larotrectinib will increase the level or effect of isavuconazonium sulfate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- istradefylline
istradefylline will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Istradefylline 40 mg/day increased peak levels and AUC of CYP3A4 substrates in clinical trials. This effect was not observed with istradefylline 20 mg/day. Consider dose reduction of sensitive CYP3A4 substrates.
- ivacaftor
larotrectinib will increase the level or effect of ivacaftor by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Reduce ivacaftor dose if coadministered with moderate CYP3A4 inhibitors. See specific ivacaftor-containing product for precise dosage modification.
- lefamulin
larotrectinib will increase the level or effect of lefamulin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Monitor for adverse effects if lefamulin is coadministered with moderate CYP3A inhibitors.
- levamlodipine
larotrectinib will increase the level or effect of levamlodipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration with moderate and strong CYP3A inhibitors results in increased systemic exposure to amlodipine and may require dose reduction. Monitor for symptoms of hypotension and edema when amlodipine is coadministered with CYP3A inhibitors to determine the need for dose adjustment.
- oliceridine
larotrectinib will increase the level or effect of oliceridine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. If concomitant use is necessary, may require less frequent oliceridine dosing. Closely monitor for respiratory depression and sedation and titrate subsequent doses accordingly. If inhibitor is discontinued, consider increase oliceridine dosage until stable drug effects are achieved. Monitor for signs of opioid withdrawal.
- rimegepant
larotrectinib will increase the level or effect of rimegepant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Avoid repeating rimegepant dose within 48 hr if coadministered with a moderate CYP3A4 inhibitor.
- rucaparib
rucaparib will increase the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Adjust dosage of CYP3A4 substrates, if clinically indicated.
- siponimod
siponimod and larotrectinib both increase immunosuppressive effects; risk of infection. Use Caution/Monitor. Caution if coadministered because of additive immunosuppressive effects during such therapy and in the weeks following administration. When switching from drugs with prolonged immune effects, consider the half-life and mode of action of these drugs to avoid unintended additive immunosuppressive effects.
- tazemetostat
tazemetostat will decrease the level or effect of larotrectinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.
- tucatinib
tucatinib will increase the level or effect of larotrectinib by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor. Consider reducing the dosage of P-gp substrates, where minimal concentration changes may lead to serious or life-threatening toxicities.
- voclosporin
larotrectinib will increase the level or effect of voclosporin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Reduce voclosporin daily dosage to 15.8 mg PO in AM and 7.9 mg PO in PM.
- zanubrutinib
larotrectinib will increase the level or effect of zanubrutinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Reduce zanubrutinib dose when coadministered with a moderate CYP3A4 inhibitor. Interrupt dose as recommended for adverse reactions. After discontinuing the CYP3A4 inhibitor, resume previous dose of zanubrutinib. See zanubrutinib Dosage Modifications for precise recommendation.
Minor (0)
Adverse Effects
All grades of severity are listed unless indicated
>10%
Increased AST/ALT (45%)
Anemia (42%)
Fatigue (37%)
Hypoalbuminemia (35%)
Increased alkaline phosphatase (30%)
Nausea (29%)
Dizziness (28%)
Vomiting (26%)
Cough (26%)
Constipation (23%)
Neutropenia (23%)
Diarrhea (22%)
Pyrexia (18%)
Dyspnea (18%)
Peripheral edema (15%)
Increased weight (15%)
Headache (14%)
Arthralgia (14%)
Myalgia (14%)
Muscular weakness (13%)
Decreased appetite (13%)
Abdominal pain (13%)
Back pain (12%)
Pain in extremity (12%)
Hypertension (11%)
1-10%
Nasal congestion (10%)
Fall (10%)
Anemia, Grade 3 or 4 (10%)
Neutropenia, Grade 3 or 4 (7%)
Increased weight, Grade 3 or 4 (4%)
Fatigue, Grade 3 or 4 (3%)
Increased alkaline phosphatase, Grade 3 or 4 (3%)
Increased AST/ALT, Grade 3 or 4 (45%)
Diarrhea, Grade 3 or 4 (2%)
Dyspnea, Grade 3 or 4 (2%)
Decreased appetite, Grade 3 or 4 (2%)
Hypertension, Grade 3 or 4 (2%)
Hypoalbuminemia, Grade 3 or 4 (3%)
Pyrexia, Grade 3 or 4 (1%)
Nausea, Grade 3 or 4 (1%)
Vomiting, Grade 3 or 4 (1%)
Arthralgia, Grade 3 or 4 (1%)
Myalgia, Grade 3 or 4 (1%)
Back pain, Grade 3 or 4 (1%)
Pain in extremity, Grade 3 or 4 (1%)
Fall, Grade 3 or 4 (1%)
Constipation, Grade 3 or 4 (1%)
Dizziness, Grade 3 or 4 (1%)
Warnings
Contraindications
None
Cautions
Increased transaminases of any grade occurred; median time to onset of increased AST/ALT was 2 months; monitor liver tests every 2 weeks during first month of treatment, then monthly thereafter, and as clinically indicated
Can cause fetal harm
Skeletal fractures reported; promptly evaluate patients with signs or symptoms of potential fracture (eg, pain, changes in mobility, deformity); no data are available on effects on healing of known fractures or risk of future fractures
CNS effects
- CNS adverse reactions (eg, dizziness, cognitive impairment, mood disorders, sleep disturbances)
- Cognitive impairment included memory impairment, confused state, disturbance in attention, delirium, and cognitive disorders; median onset time: 5.6 months (range: 2 days to 41 months)
- Mood disorders included anxiety, depression, agitation, and irritability; median onset time: 3.9 months (range: 1 day to 40.5 months)
- Consult on the risks; advise patients not to drive or operate hazardous machinery if experiencing neurologic adverse reactions
- Withhold or permanently discontinue based on severity
- If withheld, modify dosage when resumed
Drug interaction overview
- Major CYP3A4 substrate; also a P-gp and BCRP substrate
- Moderately inhibits CYP3A4
-
Strong CYP3A4 inhibitors
- Avoid coadministration, including grapefruit or grapefruit juice
- Strong CYP3A4 inhibitors may increase larotrectinib plasma concentrations and potentially result in higher incidence of adverse reactions
- If unavoidable, modify dose as recommended
-
Strong CYP3A4 inducers
- Avoid coadministration
- Strong CYP3A4 inducers may decrease larotrectinib plasma concentrations, which may decrease efficacy
- If unavoidable, modify dose as recommended
-
Sensitive CYP3A4 substrates
- Avoid coadministration
- Larotrectinib may increase plasma concentrations of sensitive CYP3A4 substrates, which may increase incidence and/or severity of adverse reactions
- If unavoidable, monitor for increased adverse reactions of drugs that are sensitive CYP3A4 substrates
Pregnancy
Pregnancy
Based on literature reports, findings from animal studies, and its mechanism of action, embryofetal harm may occur when administered to pregnant females
There are no available data on use in pregnant females
Verify pregnancy status in females of reproductive potential before initiation
Animal data
- Administration to pregnant rats and rabbits during organogenesis resulted in malformations at maternal exposures were ~11- and 0.7-times (observed at 100 mg PO BID)
Contraception
- Females of reproductive potential: Use effective contraception during treatment and for at least 1 week after last dose
- Males with female partners of reproductive potential: Use effective contraception during treatment and for 1 week after last dose
Infertility
- Based on histopathological findings in reproductive tracts of female rats in a 1-month repeated-dose study, fertility may be reduced
Lactation
There are no data on presence of larotrectinib or its metabolites in human milk and its effects on breastfed children or on milk production
Advise females not to breastfeed during treatment and for 1 week after final dose
Pregnancy Categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk. C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done. D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk. X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist. NA: Information not available.Pharmacology
Mechanism of Action
Highly selective inhibitor of tropomyosin receptor kinases (TRK), TRKA, TRKB, and TRKC
TRKA, B, and C are encoded by the genes NTRK1, NTRK2, and NTRK3; chromosomal rearrangements involving in-frame fusions of these genes with various partners can result in constitutively-activated chimeric TRK fusion proteins that can act as an oncogenic driver, promoting cell proliferation and survival in tumor cell lines
In tumor models, larotrectinib demonstrates antitumor activity in cells by activation of TRK proteins resulting from gene fusions, deletion of a protein regulatory domain, or in cells with TRK overexpression
Absorption
Steady-state reached within 3 days
Peak plasma concentration: 788 ng/mL (capsule)
Peak plasma concentration of oral solution was 36% higher in healthy subjects compared with capsules
Peak plasma time: 1 hr (capsule)
AUC: 4351 ng·hr/mL (capsule; similar with oral solution)
Bioavailability: 34%
Distribution
Vd (steady-state): 48 L
Protein bound: 70%
Metabolism
Metabolized predominantly by CYP3A4
Elimination
Half-life: 2.9 hr
Clearance: 98 L/hr
Excretion: Feces (58% [5% unchanged]); urine (39% [20% unchanged])
Pharmacogenomics
Selecting patients for treatment is based on the presence of a NTRK gene fusion in solid tumor specimens
Administration
Oral Administration
Take with or without food
Swallow capsules whole with water; do not chew or crush
Capsules or oral solution may be used interchangeably
Missed dose (within 6 hr of next scheduled dose): Do not make up missed dose
Vomit dose: Take next dose at scheduled time
Storage
Capsules: Store at room temperature 20-25ºC (68-77ºF); excursions permitted to 15-30°C (59-86°F)
Oral solution: Refrigerate at 2-8°C (36-46°F); do not freeze; discard any oral solution remaining after 90 days of first opening bottle
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Formulary
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Adding plans allows you to:
- View the formulary and any restrictions for each plan.
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- Compare formulary status to other drugs in the same class.
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