Revisiting a lower starting dose of alectinib in ALK-Positive non-small cell lung cancer.

We present here a case of ALK-positive lung adenocarcinoma that has been started on Alectinib. Treatment has been initiated at the recommended initial dose, but it subsequently required a dose adjustment following adverse drug events. Alectinib is a second-generation, CNS-active, tyrosine kinase inhibitor used in the treatment of ALK-positive non-small cell lung cancer. Its efficacy as a first-line treatment and as a second-line agent after Crizotinib has been proven across several trials both in terms of overall response rate and progression-free survival. The use of Alectinib is associated with side effects that occasionally lead to treatment discontinuation, interruption, or dose adjustment. Several studies have used two starting doses - 300 mg and 600 mg twice daily - across different populations and have consistently shown efficacy of Alectinib for both treatment doses. Results of these studies have also revealed that body weight, rather than race, affect the pharmacokinetics of Alectinib. Randomized trials have shown that the 600 mg dose is associated with more grade ≥3 adverse events and more changes in treatment in contrast to the 300 mg dose. A lower dose of Alectinib may limit treatment disruptions and dose reductions particularly for specific patient populations-particularly those with a lower body weight.