What Is Entrectinib (Rozlytrek)? Uses, Dosage, and What You Need to Know in 2026

Entrectinib — sold under the brand name Rozlytrek — is a targeted cancer therapy that was approved by the FDA in August 2019. It belongs to a class of drugs called tyrosine kinase inhibitors (TKIs) and is specifically designed to block the abnormal proteins that drive certain rare cancers. Here's everything you need to know about what it treats, how it's dosed, and what it means for your care.

What Cancer Does Entrectinib Treat?

Entrectinib is FDA-approved for two specific indications, both of which require molecular biomarker testing to confirm eligibility:

ROS1-positive metastatic non-small cell lung cancer (NSCLC): For adult patients whose lung cancer harbors a ROS1 gene rearrangement, as confirmed by an FDA-approved test. ROS1 fusions occur in roughly 1–2% of all NSCLC cases, making this a relatively rare subgroup.

NTRK gene fusion-positive solid tumors: For adult and pediatric patients older than 1 month with solid tumors that have an NTRK1, NTRK2, or NTRK3 gene fusion (confirmed by FDA-approved test, without a known acquired resistance mutation), that are metastatic or where surgery would cause severe harm, and that have progressed on prior treatment or have no satisfactory alternative.

The NTRK fusion indication is what makes entrectinib a "tumor-agnostic" therapy — it can potentially treat many different types of cancer (lung, salivary gland, breast, thyroid, colorectal, sarcoma, and others) as long as they carry an NTRK gene fusion.

What Is a ROS1 or NTRK Gene Fusion?

Gene fusions occur when two genes become abnormally joined together due to a chromosomal rearrangement. When the ROS1 or NTRK genes fuse with other genes, they can create constantly active proteins that drive tumor growth — a phenomenon called "oncogene addiction." Entrectinib works by binding to these abnormal fusion proteins and blocking their activity, essentially starving the tumor of the signal it depends on to survive and grow.

How Is Entrectinib Taken?

Entrectinib is an oral medication taken once daily. It comes in three formulations:

100 mg hard capsules (yellow)

200 mg hard capsules (orange)

50 mg oral pellets (film-coated pellets in packets) — particularly useful for pediatric patients or those who cannot swallow capsules

What Is the Standard Dose of Entrectinib?

Adults: 600 mg orally once daily (three 200 mg capsules or six 100 mg capsules)

Pediatric patients (NTRK indication): Dose is based on body surface area (BSA); ranges from 250 mg/m² (for those under 6 months) to 600 mg/m² (for those 6 months and older, depending on BSA)

Capsules should be swallowed whole with water — do not open, crush, or chew. Pellets are sprinkled on soft food (such as applesauce) and swallowed within 20 minutes. The medication can be taken with or without food.

How Does Entrectinib Work in the Body?

Entrectinib is a selective multikinase inhibitor that targets the TrkA, TrkB, and TrkC proteins (encoded by NTRK1, NTRK2, and NTRK3 genes respectively), ROS1, and ALK kinases — all with high potency at nanomolar concentrations. Importantly, it was designed to cross the blood-brain barrier, giving it activity against CNS metastases in addition to systemic disease.

Is Entrectinib a Controlled Substance?

No. Entrectinib (Rozlytrek) is not a DEA-scheduled controlled substance. However, it is a prescription-only specialty medication that requires prior authorization from your insurer and must be obtained through a designated specialty pharmacy.

How Effective Is Entrectinib?

In the integrated analysis of clinical trials supporting FDA approval for ROS1-positive NSCLC, entrectinib achieved an overall response rate of approximately 68–78% in first-line patients, with a median progression-free survival of 15–17 months. In CNS metastasis subgroups, 5 out of 7 patients showed CNS response, demonstrating the drug's ability to penetrate the brain. For NTRK fusion-positive solid tumors, pooled analyses showed durable response rates across diverse tumor types.

The Bottom Line

Entrectinib (Rozlytrek) is a remarkable targeted therapy that can be effective across many cancer types as long as the right biomarker is present. To understand in more detail how entrectinib works at the molecular level, see our guide on how entrectinib works — mechanism of action explained. Once you have a prescription, medfinder can help you find a pharmacy that can fill it.