Will tumors grow rapidly after stopping the targeted drug dacomitinib/dacomitinib?

Dacomitinib/Dacomitinib (Dacomitinib), as an EGFR-TKI (tyrosine kinase inhibitor), is mainly used to treat patients with EGFR mutation-positive non-small cell lung cancer (NSCLC). It inhibits the growth and division of tumor cells by inhibiting the kinase activity of mutant EGFR. The therapeutic effect of dacomitinib has been verified in multiple clinical studies, but the effect after discontinuation of the drug is still a matter of concern.

Clinically, patients typically experience a phase of significant tumor control when treated with dacomitinib. However, once the drug is discontinued, tumor recurrence and progression are possible, especially if effective follow-up treatment is not taken. Tumor cells may develop drug-resistant mutations as they adapt to the effects of targeted drugs, resulting in a weakened therapeutic effect. Such drug-resistant mutations may allow tumors to grow again within a short period of time, possibly even more severely than without treatment.

It is worth noting that in clinical practice, dacomitinib will not immediately cause "explosive" growth of tumors once the drug is discontinued. The rate of tumor growth will vary depending on individual patient differences, the type and stage of the tumor, and many other factors. Some patients may maintain stable disease for a long time after stopping the drug, but some patients experience disease progression within a few months after stopping the drug. Therefore, for patients with known drug-resistant mutations, treatment may need to be resumed as soon as possible after drug discontinuation, or other targeted drugs or immunotherapy may be considered as follow-up treatment.

In summary, whether the tumor will grow rapidly after dacomitinib is discontinued depends on a variety of factors, including the patient's physical condition, the tumor's drug resistance, and whether follow-up treatment is started in a timely manner. For most patients, there is a risk of tumor growth after stopping the drug, so caution and close communication with the doctor are needed when stopping the drug.

Reference materials:https://www.pfizer.com/products/product-detail/vizimpro