AstraZeneca and Daiichi Sankyo’s Enhertu drug is on a hot streak, winning FDA approval for lung cancer, marking the second positive regulatory decision in a week.
The The FDA approval was announced Friday covers the treatment of adults whose advanced cases of non-small cell lung cancer (NSCLC) express the cancer protein HER2. These cancers must have received at least one prior systemic therapy. According to the FDA, Enhertu is now the first drug approved for the treatment of NSCLC characterized by a HER2 mutation. Concurrent with Enhertu’s new approval, the agency also approved a Companion Diagnostics Thermo Fisher Scientific who discovered this mutation.
Enhertu is an antibody-drug conjugate, a type of therapy consisting of a targeted antibody bound to a toxic drug. The antibody component of Enhertu is designed to target HER2, a protein expressed on the surface of some cancer cells. The drug won its first FDA approval in 2019 to treat HER2-positive breast cancer that has spread. On Aug. 6 The FDA expanded the drug’s approval to include the treatment of breast cancer characterized by levels of HER2 that were previously considered too low for targeted therapy. This decision defined a new category of breast cancer patients, providing them with their first targeted therapy.
Enhertu’s latest approval means the drug can now be used to treat the most common type of lung cancer. NSCLC accounts for about 80% of lung cancer cases, according to the American Lung Association. This approval was based on an interim analysis of data from phase 2 data that included 152 participants with HER2-positive NSCLC. The primary objective of the study was to measure the objective drug response rate, defined as the percentage of patients showing either a complete response or a partial response to the infused therapy. The objective response rate was 58% and the median duration of this response was 8.7 months. Response rates were consistent at both doses tested. Higher rates of pulmonary complications were observed at the higher dose; the approval covers the low dose. AstraZeneca said that the results of the NSCLC clinical trial will be presented at a future medical meeting.
The most common side effects reported in the clinical trial included nausea, low white blood cell counts, anemia and low levels of immune cells called neutrophils — all consistent with previous tests of the drug. The most serious complication seen in the study was interstitial lung disease, which is characterized by scarring and inflammation. The drug’s label includes a boxed warning noting this side effect.
“HER2-mutant non-small cell lung cancer is an aggressive form of the disease that typically affects young patients who have previously faced limited treatment options and a poor prognosis,” said Dave Fredrickson, executive vice president of AstraZeneca’s oncology business, in prepared statement. “Today’s news provides these patients with the opportunity to benefit from targeted therapy and highlights the importance of testing for predictive markers, including HER2 in lung cancer, at the time of diagnosis to ensure patients receive the most appropriate treatment for their specific disease.’
The regulatory decision for Enhertu in NSCLC is an accelerated approval, which is based on less evidence than required for standard approval. AstraZeneca and Daiichi Sankyo will need to conduct further clinical trials to confirm the drug’s benefit to patients. The drug’s first approval in HER2-positive breast cancer was fast-tracked. That status was converted to full approval in May, when the drug moved up the chain of cancer treatment options with the FDA’s approval of the drug as a second-line therapy. Enhertu is also approved for the treatment of advanced HER2-positive stomach cancer.
Here’s a roundup of some additional regulatory news from last week:
—Tabrecta, a Novartis drug that won fast track approval in 2020 for the treatment of advanced NSCLC, now has full FDA approval. The targeted therapy is a small molecule designed to target a specific genetic signature known as mesenchymal-epithelial transition (MET) exon 14 skipping. Change the status of the drug to full approval is based on additional clinical testing that shows response rates consistent with earlier data.
— The European Medicines Agency has told ProQR Therapeutics that the company must conduct another clinical trial for its RNA therapy for a rare eye disease. The therapy failed a major study earlier this year, but ProQR hoped that additional analysis of the clinical data would be sufficient to support a regulatory submission. Instead of conducting another survey, The Netherlands-based biotech said it would seek a partnership with all of its ophthalmic assets and to shift its focus to developing drugs for liver and central nervous system disorders based on its RNA platform technology.
— The FDA rejected an application by Acadia Therapeutics that wanted to expand the approval of its antipsychotic Nuplazid to include Alzheimer’s psychosis. According to Acadia, the FDA said the data provided was not from an adequate and well-controlled study and the company must conduct another clinical trial. The drug was first approved in 2016 as a treatment for hallucinations and delusions experienced by patients with Parkinson’s disease.
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