Amgen criticized for profit-driven Lumakras dosing

US Senator Richard Durbin has raised concerns about Amgen's decision to continue prescribing a higher dose for its lung cancer drug, Lumakras (sotorasib). In a letter addressed to Amgen's CEO Robert Bradway on May 10, Durbin accused the pharmaceutical company of prioritizing profits over patient health. He argued that Amgen's dosing strategy appears to downplay the severe side effects associated with the higher dose of Lumakras, which received FDA accelerated approval in 2021 for treating KRAS-mutated non-small-cell lung cancer (NSCLC) in second-line therapy. The drug was initially launched at a list price of $17,900 per month.

Recent developments have put Amgen under scrutiny. In December, the FDA denied Amgen's request for full approval of Lumakras due to unclear survival data, following advice from an advisory panel. As a result, the FDA has mandated that Amgen complete a new confirmatory study of the KRAS inhibitor by February 2028.

Senator Durbin's letter criticizes Amgen for marketing Lumakras at a daily dose of 960mg, despite findings from a post-marketing study required by the FDA. This study compared the safety and efficacy of the 960mg dose with a lower dose of 240mg. The results, released last October, indicated that the 240mg dose had similar efficacy but significantly reduced toxicity and adverse events. Despite this, Amgen chose to maintain the 960mg dosage in its approved labeling.

"An apparent reason to maintain the 960mg dosage would be to maximise Amgen's profits," Durbin wrote. He pointed out that reducing the dosage to 240mg would mean patients would consume only a quarter of the pills, potentially reducing Amgen's revenue by 75%. Durbin also noted that the higher dosage was associated with nearly double the rate of serious or life-threatening adverse effects. He highlighted the financial burden on patients and taxpayers, mentioning that Medicare spent $124 million on Lumakras in 2022 alone.

Amgen, in response to FirstWord, defended its decision, stating that data from various clinical trials and real-world evidence showed that lung cancer patients benefit from the once-daily 960mg dose. The company claimed that the FDA-required study showed that the higher dose had a more favorable benefit-risk profile compared to the lower dose. Amgen emphasized that these findings support the FDA-approved 960mg dose for KRAS G12C advanced NSCLC. The company also mentioned it would adhere to a June 10 deadline to respond to Senator Durbin's inquiries outlined in his letter.

In summary, the dispute between Senator Durbin and Amgen centers on the dosage strategy for Lumakras. While Durbin accuses Amgen of putting profits before patient well-being, Amgen argues that the higher dose is backed by clinical data and offers a better benefit-risk profile. The controversy has highlighted broader concerns about drug pricing and its impact on patients and healthcare systems.