Lurbinectedin is a medication used to treat metastatic small cell lung cancer (SCLC) in adult patients whose disease has progressed after initial chemotherapy. The drug is administered intravenously, and the dosage is determined based on the patient's body surface area (BSA).

There is no specific dosage adjustment for elderly patients mentioned in the sources provided. However, caution should be exercised when administering lurbinectedin to elderly patients, as they may be more susceptible to the drug's side effects.

According to the drug's label [2], the most common adverse reactions observed in patients receiving lurbinectedin were myelosuppression, fatigue, increased creatinine, increased alanine aminotransferase, increased glucose, nausea, decreased appetite, musculoskeletal pain, decreased albumin, constipation, dyspnea, decreased sodium, increased aspartate aminotransferase, vomiting, cough, decreased magnesium, diarrhea, decreased potassium, decreased calcium, rash, and pyrexia.

In a phase II clinical trial [3], which included patients aged 65 years and older, the safety and efficacy of lurbinectedin were evaluated. The study concluded that lurbinectedin was well-tolerated in elderly patients, and the safety profile was consistent with that observed in the overall study population.

In summary, there is no specific dosage adjustment for lurbinectedin in elderly patients. However, caution should be exercised when administering the drug to this population due to the potential for increased susceptibility to side effects. The most common adverse reactions observed in patients receiving lurbinectedin are myelosuppression, fatigue, and increased creatinine. A phase II clinical trial has shown that lurbinectedin is well-tolerated in elderly patients.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LURBINECTEDIN
[2] https://www.accessdata.fda.gov/drugsatfda_docs/label/2020/213702s000lbl.pdf
[3] https://www.sciencedirect.com/science/article/pii/S1556086419307364