(Solid Tumors) ASCO 2020: ARROW Trial Report on the RET Inhibitor Pralsetinib in RET Fusion-Positive Solid Tumors
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This article is a summary of international medical information and is not medical advice; it cannot replace the diagnosis or treatment plan of your attending physician. The medical technologies, drug information and clinical data presented here are compiled from public literature and official statements of Japanese medical institutions; the applicability and outcome of any therapy vary with each patient and must be assessed individually by a qualified physician.
Regulatory status in Japan (checked November 4, 2026): Pralsetinib is not approved in Japan; no Japanese marketing approval or Japanese package insert was found. This article only summarizes overseas research reports. It is not an assessment of the treatment and is not medical or treatment advice.
- Originally posted: May 29, 2020
At the ASCO 2020 Virtual Scientific Program (May 29–31, 2020), Dr. Vivek Subbiah reported data from the ARROW Phase 1/2 clinical trial of the RET inhibitor pralsetinib (BLU-667) in patients with advanced solid tumors harboring RET fusions.
Trial design
- Pralsetinib 30–600 mg once or twice daily
- Primary endpoint: objective response rate
- Patients: papillary carcinoma 16, anaplastic thyroid cancer 1, pancreatic cancer 3, colorectal cancer 3, other tumor types 6
Reported results
- Objective response rate: thyroid cancer group 75% (9 of 12); other tumor types 3 of 5
- Median duration of response: thyroid cancer group 14.5 months; other tumor types (2 patients) 11.5 and 19.3 months
- Common adverse events: AST increase 31%, anemia 22%, ALT increase 21%, constipation 21%, hypertension 20%; discontinuation due to adverse events 4%
Points to consider
These are early-phase data presented at a conference, with very few patients per tumor type, and they cannot be used to predict outcomes for individual patients. Pralsetinib is not approved in Japan.
Source: Subbiah V, et al. 2020 ASCO Virtual Scientific Program, Abstract No. 109
Note: This article summarizes overseas clinical research for reference only and is not medical or treatment advice. Study data do not predict outcomes for individual patients. Please refer to the original source and discuss any treatment decisions with your physician.
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