Jemperli (Dostarlimab)

Jemperli is indicated for cancers characterized by deficient mismatch repair (dMMR) or high microsatellite instability (MSI‑H).

• Advanced dMMR endometrial cancer: improves disease control in adults whose cancer has progressed after prior therapy.
• MSI‑H solid tumours: provides a therapeutic option for metastatic or unresectable tumours that are MSI‑high and have failed standard treatments.

• Dostarlimab is a humanized IgG4 monoclonal antibody that binds selectively to the programmed death‑1 (PD‑1) receptor on T cells. By blocking PD‑1 interaction with its ligands PD‑L1 and PD‑L2, the drug restores T‑cell activation and enhances immune‑mediated attack on tumour cells, thereby promoting anti‑tumour immunity.

Adverse reactions may range from mild to severe and are monitored throughout therapy.

Common Side Effects

• Fatigue: persistent tiredness reported by many patients.
• Nausea: occasional feeling of sickness or upset stomach.
• Diarrhoea: loose stools that may require supportive care.
• Infusion‑related reactions: flushing, chills, or mild hypotension during administration.
• Rash: skin erythema or pruritus.
• Hypothyroidism: reduced thyroid hormone production detected on labs.

Serious or Rare Side Effects

• Immune‑mediated pneumonitis: inflammation of lung tissue that can be life‑threatening.
• Hepatitis: immune‑related liver injury presenting with elevated enzymes.
• Colitis: severe inflammation of the colon causing abdominal pain and diarrhoea.
• Severe infusion reactions: anaphylaxis or bronchospasm requiring emergency intervention.
• Endocrinopathies: adrenal insufficiency or type 1 diabetes onset.
• Myocarditis: inflammation of heart muscle with potential cardiac dysfunction.

Patients receiving Jemperli should be monitored closely for immune‑related toxicities and other safety considerations.

• Monitor for immune‑mediated adverse events: assess organ function regularly.
• Assess thyroid function before and during treatment: check TSH and free T4 levels.
• Evaluate pre‑existing autoimmune disease: weigh risks versus benefits.
• Conduct baseline laboratory tests: complete blood count, liver enzymes, and renal function.
• Avoid live vaccines during therapy: they may cause infection.
• Store at 2-8°C: keep refrigerated, protect from light, do not freeze or shake.

Dostarlimab may interact with other agents that affect immune function or increase infection risk.

Major Interactions (Avoid)

• Concurrent PD‑1/PD‑L1 inhibitors: additive immune activation can raise toxicity.
• High‑dose systemic steroids: may diminish therapeutic efficacy.
• Live attenuated vaccines: risk of uncontrolled infection.

Moderate Interactions (Monitor Closely)

• Other immunomodulatory drugs (e.g., CTLA‑4 inhibitors): monitor for overlapping immune‑related events.
• Anticoagulants: watch for bleeding if severe thrombocytopenia occurs.
• Hormone replacement therapy: adjust dosing if endocrine dysfunction develops.