How does Retevmo work?

Retevmo is a selective RET kinase inhibitor that blocks certain enzymes to slow the growth of cancers caused by abnormal RET genes. Blocking RET in cancer tumors can slow cancer growth. Patients are selected for treatment with Retevmo based on a specific biomarker test.

Retevmo is considered a targeted drug therapy that blocks specific pathways that allow cancer to grow uncontrolled. It is used to treat:

• RET (rearranged during transfection) gene fusion positive advanced or metastatic non-small cell lung cancer (NSCLC) in adults.
• Advanced or metastatic medullary thyroid cancer (MTC) with a RET mutation in adults and children 2 years and older who require systemic (body-wide) therapy.
• Advanced or metastatic thyroid cancer with a RET gene fusion in adults and children 2 years and older who require systemic (body-wide) therapy and who have received radioactive iodine and it did not work or is no longer working (if radioactive iodine is appropriate).
• Other solid tumors with RET gene fusions in adults and children 2 years and older with advanced or metastatic RET-driven tumors, that have progressed on or following prior systemic treatment or who have no satisfactory alternative treatment options.

The uses for medullary thyroid cancer and solid tumors are all approved under FDA-accelerated approval based on overall response rate and duration of response. Continued approval may depend upon proven clinical benefit in further confirmatory trials.

In solid tumor studies, the most commonly included cancers were pancreatic adenocarcinoma (27%), colorectal (24%), salivary (10%) and unknown primary (7%).

What is the mechanism of action for Retvmo?

The mechanism of action of Retevmo involves turning off the production of RET in RET-driven cancers. Abnormal alterations in genes can cause cancer growth. One gene that may change is called RET (rearranged during transfection) and it has been identified in certain types of cancer.

RET is normally used to help our cells to talk to each other (called “cell signaling") to ensure healthy cell functioning, but if you have a gene change, RET can be activated non-stop to lead to uncontrolled cancer cell growth. Blocking RET in cancer tumors can slow cancer growth.

RET genes in cancer can fuse to another gene and this is called RET fusion. RET can be found in lung cancer, thyroid tumors and other solid cancers (such as pancreatic cancer, colon cancer, and breast cancer).

Is Retevmo a chemotherapy drug?

No, Retevmo is considered a targeted drug therapy, not a traditional chemotherapy agent. It is given by mouth as an oral capsule or tablet, not through a vein.

Targeted drug therapy like Retevmo works by blocking specific pathways that allow the cancer to grow uncontrolled. Targeted drug therapies find and attack specific types of cancer cells and may cause less damage to healthy cells; however, common and serious side effects may still occur, even to healthy cells.

Chemotherapy works by killing rapidly growing cancer cells, but can also adversely affect normal cells.

Retevmo may cause serious side effects, such as severe or life-threatening problems with your lungs (inflammation / swelling), liver, heart, thyroid or other body systems. It can cause problems with high blood pressure, heart rhythm changes, would healing, or bleeding. Serious allergic reactions can also occur.

Related questions

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Common side effects in adults

Common side effects with Retevmo in at least 25% of adults patients with solid tumors include: fluid retention (swelling or edema), diarrhea, fatigue (tiredness), dry mouth, high blood pressure (hypertension), stomach area (abdominal) pain, constipation, rash, nausea, and headache.

Laboratory changes (grade 3 or 4) in at least 5% of adults with solid tumors include: decreased lymphocytes (white blood cells that help fight infection), increased alanine aminotransferase (ALT, a liver enzyme), increased aspartate aminotransferase (AST, a liver enzyme), decreased sodium and decreased calcium.

Common side effects in children

The most common adverse reactions in at least 25% of children with solid tumors include: musculoskeletal (muscle or bone) pain, diarrhea, headache, nausea, vomiting, coronavirus infection (COVID-19), abdominal (stomach) pain, fatigue (tiredness), pyrexia (fever), and hemorrhage (bleeding).

Laboratory changes (grade 3 or 4) in at least 5% of children with solid tumors include decreased calcium, decreased hemoglobin (oxygen-carry protein your red blood cells), and decreased neutrophils (a type of white blood cell that helps to fight infection).

Your doctor or pharmacist should give you a handout to learn how to recognize Retevmo side effects and when you should call your doctor. If you do not have one, ask them for a copy.

This is not a complete list of side effects. Talk to your doctor about what you should expect for side effects during treatment.

Learn More: Side Effects and Warnings for Retevmo

How do I take Retvmo?

Retevmo is given as an oral capsule or tablet taken twice daily (approximately every 12 hours) until your disease worsens or you experience intolerable side effects. You can take it with or without food. Swallow your medicine whole, do not crush or chew it.

Your doctor will determine your dose, which is based on your weight. Always take your medicine exactly as your doctor prescribes it.

The generic name for Retevmo (pronounced reh-TEHV-moh) is selpercatinib. It is manufactured by Eli Lilly and was first approved in May 2020.

This is not all the information you need to know about Retevmo for safe and effective use and does not take the place of your doctor’s directions. Review the full Retevmo product information and discuss any questions you have with your doctor or other health care provider.