Qinlock 50 mg Tablet

Qinlock 50mg Tablet (Ripretinib) – World’s First Switch-Control KIT/PDGFRA Inhibitor | NCCN Category 1 for Advanced GIST

Reviewed by a qualified oncologist | Last updated: April 2026 Prescription-only | Oncologist supervision mandatory | KIT/PDGFRA mutation testing recommended

What It Is

Qinlock 50mg contains Ripretinib — a novel oral kinase inhibitor developed by Deciphera Pharmaceuticals LLC (Waltham, MA, USA). FDA-approved May 15, 2020, Qinlock is the world’s first and only switch-control kinase inhibitor — a mechanism that is categorically different from all previous GIST tyrosine kinase inhibitors.

Qinlock is available as 50mg film-coated tablets. The recommended dose is 150mg once daily (three 50mg tablets), taken with or without food.

Important: Qinlock is the originator branded product. No FDA-approved generic or biosimilar exists as of 2026. Patients purchasing from international pharmacy exporters are receiving the genuine originator product at export pricing.

The Switch-Control Difference — Why This Matters

All prior GIST TKIs (imatinib, sunitinib, regorafenib) are type II kinase inhibitors — they occupy the ATP-binding pocket to block kinase activity. Their limitation: as KIT and PDGFRA accumulate resistance mutations across treatment lines, the ATP pocket changes shape and these inhibitors lose binding — causing disease progression.

Ripretinib works differently. It is a switch-control inhibitor — it simultaneously occupies both the ATP-binding switch pocket AND the activation loop of KIT and PDGFRA. This dual-site binding locks the kinase in its inactive conformation regardless of which resistance mutations have accumulated. By targeting the switch-control region — which is required for kinase activation regardless of mutation — ripretinib broadly inhibits primary, secondary, and treatment-resistant KIT and PDGFRA variants.

This is why Qinlock works where prior TKIs have failed: it is designed for heavily mutated, multi-drug-resistant GIST.

Indications

INVICTUS trial (4th-line, Phase 3): Median PFS 6.3 months vs 1.0 month for placebo (HR 0.15; p<0.0001). Median OS 15.1 months vs 6.6 months. Disease control rate 76.4%.

INTRIGUE trial (2nd-line): In KIT exon 11 mutant patients, ripretinib 150mg showed superior outcomes vs sunitinib — underpinning the FDA Breakthrough Therapy Designation granted 2023.

Dosage

150mg (three 50mg tablets) orally once daily — with or without food. Take at the same time each day. Swallow whole.

Missed dose: Take if less than 8 hours have passed. Otherwise skip — do not double dose.

Dose reductions for toxicity: First reduction → 100mg (two 50mg tablets) once daily Second reduction → 50mg once daily Third → discontinue

No dose adjustment for mild/moderate renal or hepatic impairment. Avoid strong CYP3A inducers (rifampicin, carbamazepine, St. John’s Wort) — significantly reduce ripretinib exposure.

Side Effects

Very common: Alopecia (hair loss — 52%). Fatigue. Nausea. Abdominal pain. Constipation. Myalgia. Palmar-plantar erythrodysesthesia (hand-foot syndrome). Decreased appetite.

Serious — report immediately: New skin lesions or changes (cutaneous squamous cell carcinoma and melanoma reported). Cardiac dysfunction — monitor LVEF at baseline and during therapy. Hypertension. Wound healing complications — withhold for at least 1 week before elective surgery.

Embryo-foetal toxicity: Effective contraception required during treatment and for 1 week after last dose (female patients) and 1 week after last dose (male patients with female partners of reproductive potential).

References

1. Qinlock (Ripretinib) — FDA Prescribing Information, DailyMed (May 2020, updated 2024) https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=9f18e462-03dd-4296-a02a-a0577e3ee78d
2. Qinlock HCP Official Website — INVICTUS Efficacy Data, NCCN V1.2025 Reference https://www.qinlockhcp.com/efficacy
3. NCCN Adds Ripretinib to Guidelines for Second-line GIST — OncLive (2023) https://www.onclive.com/view/nccn-adds-ripretinib-to-guidelines-for-second-line-treatment-of-gist