Folotyn (pralatrexate) is a chemotherapy medicine used to treat relapsed or refractory peripheral T-cell lymphoma (PTCL), a type of aggressive blood cancer affecting T-cells (a type of white blood cell). It is used in patients whose cancer has come back after or did not respond to previous treatment.

Pralatrexate belongs to a class called antifolates. It enters cancer cells and blocks a key enzyme needed for cells to make DNA, stopping them from dividing and growing.

Folotyn is given as a short intravenous (IV) injection, usually over three to five minutes, by a healthcare professional in a hospital or infusion centre.

It is given once a week for six weeks out of every seven-week treatment cycle.

Before starting Folotyn, you will be asked to take:

• Folic acid (1 mg daily by mouth) for at least 10 days before treatment to reduce side effects
• Vitamin B12 injection (1 mg) within 10 weeks before starting and every 8 to 10 weeks during treatment

These supplements are essential and must not be skipped.

Your injections are administered in a clinical setting. If you are unable to attend a scheduled appointment, contact your oncology team promptly to arrange an alternative time.

Overdose would occur in a clinical setting. The main risk is severe bone marrow suppression. Medical staff will manage this immediately with supportive care.

Storage is handled by the clinic. Folotyn vials are stored in a refrigerator between 2°C and 8°C and protected from light.

Side effects are common with chemotherapy.

Very common side effects:

• Mucositis (painful mouth sores): one of the most common and significant side effects. Regular use of folic acid and B12 reduces this risk
• Nausea and vomiting
• Fatigue
• Low red blood cells (anaemia): may cause tiredness and breathlessness
• Low white blood cells (neutropenia): increases infection risk
• Low platelets (thrombocytopenia): increases bruising and bleeding risk

Serious side effects:

• Severe infection: fever, chills, or a temperature above 38°C should be reported immediately
• Severe mucositis requiring treatment interruption

Blood tests will be done regularly to monitor your blood count.

Tell your doctor about all medicines, especially:

• Trimethoprim (an antibiotic): blocks folate metabolism and significantly worsens mucositis and bone marrow suppression. Avoid if possible
• NSAIDs (ibuprofen, naproxen): may slow kidney clearance of pralatrexate, increasing its concentration and side effects

Always inform your full medical team about all medicines including herbal and over-the-counter products.

Why do I need folic acid and vitamin B12?

Pralatrexate blocks folate pathways that cancer cells need, but normal body cells are also affected. Folic acid and vitamin B12 supplements help protect your normal cells, particularly the lining of your mouth and gut, from the toxic effects of the drug. Taking these supplements as prescribed is essential, not optional.

What should I do about mouth sores?

Use a soft toothbrush, avoid alcohol-based mouthwashes, rinse frequently with salt water or a prescribed mouthwash, and eat soft, non-irritating foods. Tell your nurse or doctor about any mouth sores as soon as they appear so they can provide appropriate treatment.

Ace provides accurate and independent information medically reviewed on prescription medications. This material is provided for educational purposes only and is not intended for medical advice, diagnosis or treatment.