When Alectinib Stops Working — Your Next Treatment Options

Brain-only progression is sometimes managed differently from progression elsewhere in the body. If disease in the brain is growing while the rest of the body remains controlled, your oncologist may consider local treatment — stereotactic radiotherapy to specific lesions, or whole-brain radiotherapy in different circumstances — rather than switching the systemic drug immediately. Lorlatinib has documented activity in the brain and may be the preferred systemic next step regardless. The right approach depends on how many brain lesions are involved, whether they are causing symptoms, and what local treatment options are available to you.

Sometimes, yes. If progression is limited to one or two sites while the rest of the disease remains stable — what is called oligoprogression — your oncologist may recommend local treatment to those sites and continue alectinib rather than switching. The reasoning is that most of the disease is still responding, and a systemic change would expose you to a new set of side effects without clear benefit in the areas still controlled. This decision depends on the number of progressing sites, how symptomatic you are, and whether local treatment is accessible to you.

In a proportion of patients, lorlatinib will eventually stop controlling the disease, and that is an honest answer to a question many families have but do not ask. The resistance mechanisms after lorlatinib are an active area of research. We do not yet have well-established standard options at that point, which is one of the reasons clinical trials at progression on lorlatinib are worth asking about. The goal of each treatment line is to maintain as much quality of life and disease control as possible for as long as possible.

Progression on a targeted therapy is one of the most appropriate moments to seek a second opinion. The question of which next treatment to use requires integrating the molecular biopsy result with treatment history, organ function, and current fitness — and an oncologist at a high-volume lung cancer centre or a molecular tumour board may see patterns that suggest an option not immediately obvious. A treating oncologist who is confident in their plan will support a second opinion, not discourage it. At CION, complex cases are reviewed in a multidisciplinary setting before next-line decisions are made.

These are two completely separate situations. Progression means the cancer has found a way around the drug — alectinib is no longer controlling the disease and a different treatment is needed. Toxicity means alectinib is causing side effects too harmful to continue, even if it is still controlling the cancer. Each situation leads to a different conversation with your oncologist about next steps. Knowing which of these applies to you helps you ask more specific questions and understand what the next recommendation is based on.

Bring the most recent scan reports, the original molecular testing result from before alectinib started, any new biopsy report if it has been done, and a list of all treatments with their start and stop dates. If a repeat biopsy has not yet been discussed, ask about it directly. Ask your oncologist three things: what drove the resistance, what are the options given that mechanism, and whether any clinical trial is relevant to your situation. Writing the answers down at the time helps — these conversations carry a great deal of information and are hard to recall fully afterwards.