NEW YORK – The National Institute for Health and Care Excellence on Tuesday said in a draft guidance that the UK's National Health Service should not provide AstraZeneca and Daiichi Sankyo's Enhertu (trastuzumab deruxtecan) to patients in England with advanced HER2-low breast cancer.
Instead, NICE's independent appraisal committee asked the drug sponsors to provide more information on Enhertu's efficacy ahead of its next meeting in early November, including more data on the treatment's ability to extend patients' lives, whether it continues to benefit patients as their disease worsens, and how these benefits compare to patients' outcomes on standard therapy.
Helen Knight, director of medicines evaluation at NICE, acknowledged in a statement that while the regulatory approval of Enhertu in HER2-low advanced breast cancer "represents a potentially significant development" for patients with limited treatment options, additional evidence is needed to help the committee make a more informed decision about the cost-effectiveness of the drug in this setting.
"Clinical trial evidence shows that trastuzumab deruxtecan increases how long people live and how long they have before their cancer gets worse compared with chemotherapy treatments used for HER2‑negative breast cancer," Knight said. "However, because there were a number of uncertainties in the company's economic model, this meant that even when taking into consideration the condition's severity and its effect on quality and length of life, the cost-effectiveness estimates were too high for it to be recommended for use in the NHS."
Each vial of Enhertu containing 100 mg of concentrate soluble powder for infusion has a list price of £1,455 ($1,770.39). The drugmakers are providing Enhertu to the NHS for late-stage HER2-positive metastatic breast cancer at an undisclosed discount, and this price would have also applied to the HER2-low breast cancer setting had NICE recommended it for this indication.
In a final draft guidance last December, NICE recommended Enhertu under a managed access scheme for patients with unresectable, metastatic HER2-positive breast cancer after at least one anti-HER2 therapy. At the time, NICE also noted the lack of evidence on Enhertu's impact on patients' survival and cost-effectiveness and decided to provide it through a managed access program to collect additional evidence.
Enhertu is approved in more than 40 countries including the US, the EU, and China for patients with unresectable metastatic HER2-low breast cancer who have had prior systemic therapy or disease recurrence during adjuvant chemotherapy or within six months of completing adjuvant chemotherapy. An estimated 1,000 HER2-low advanced breast cancer patients in England could be eligible for treatment with Enhertu if NICE ends up recommending the drug.
Evidence supporting the use of Enhertu in patients with HER2-low metastatic breast cancer comes from the Phase III DESTINY-Breast04 trial, in which the risk of disease progression or death was reduced by 50 percent for patients receiving Enhertu compared to physician's choice of chemotherapy. Median progression-free survival was 9.9 months for the Enhertu group compared to 5.1 months for those on chemotherapy.
The draft guidance is not NICE's final decision. The public has until Oct. 17 to comment on NICE's initial recommendation. The evaluation committee is slated to discuss the additional data provided by sponsors at a Nov. 7 meeting.