> ## Content Index
> Fetch the complete content index at: https://www.fdaweb.com/llms.txt
> Use this file to discover other available public pages before exploring further.

# The Impacts of Dose Interruptions on Cancer Drug Efficacy: FDA
- URL: https://www.fdaweb.com/the-impacts-of-dose-interruptions-on-cancer-drug-efficacy-fda/
- Published: 2026-11-13T17:14:08.000Z
- Updated: 2026-11-13T17:14:08.000Z
- Author: David McFarland
- Tags: Drugs

Interrupting treatment with certain lung cancer drugs may have a greater adverse effect on efficacy than reducing their dosage, according to a [new analysis](https://aacrjournals.org/clincancerres/article-abstract/doi/10.1158/1078-0432.CCR-26-1022/789866/Impact-of-Dosage-Modifications-on-Efficacy?redirectedFrom=fulltext&ref=fdaweb.com) by FDA researchers published in *Clinical Cancer Research*.

The researchers examined patient-level data from clinical trials supporting the original FDA approvals of four epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors: afatinib, dacomitinib, mobocertinib and osimertinib. All four were evaluated as monotherapy for non-small cell lung cancer with EGFR mutations.

The exploratory analysis assessed the effects of dose reductions and treatment interruptions on progression-free survival (PFS) and overall survival (OS). Researchers used time-dependent statistical models to evaluate daily drug exposure and examined early dosage modifications at 30, 60 and 90 days after treatment initiation.

Although the effects varied among the drugs, treatment interruptions, particularly those lasting four or more consecutive days, were more frequently associated with increased risks of disease progression or death than dose reductions.

The findings suggest that lowering a drug's dose to manage adverse reactions may have less impact on treatment efficacy than temporarily stopping therapy.

The researchers cautioned that the findings were limited to the four EGFR inhibitors studied and that additional research is needed to determine whether similar relationships exist for other cancer treatments, drug classes and malignancies.