The US Food and Drug Administration's (FDA) newly released draft guidance on neoadjuvant breast cancer treatments has the potential to radically change the existing pathway through which patients with aggressive early-stage breast cancer can obtain treatment, say experts.
The guidance, released on 28 May, is "intended to assist applicants in designing trials to support marketing approval of drugs to treat breast cancer in the neoadjuvant setting using pathologic complete response (pCR) as a surrogate endpoint that could support approval under the accelerated approval regulations," the agency wrote in a FederalRegister posting.
FDA had cited the "unmet need" of breast cancer patients who have aggressive strains of cancer, but who are not eligible for clinical trials which typically enroll only advanced-stage cancer patients.
In an interview with Reuters, FDA's Richard Pazdur, director of FDA's Office of Oncology Drug Products, said the goal of the guidance is to introduce potentially curative therapies to women who would otherwise require surgery to remove the cancer. "The aim of this therapy would be to cure the woman of breast cancer," Pazdur said. "It's moving a very promising drug into an early stage of the disease with a curative intent."
To assist in the development of potentially curative products, the guidance notes FDA will accept surrogate endpoints, particularly one known as pathologic complete response (pCR). The guidance document defines pCR as "the absence of any residual invasive cancer on hematoxylin and eosin evaluation of the resected breast specimen and all sampled ipsilateral lymph nodes following completion of neoadjuvant systemic therapy."
In explaining the newly-proposed definition, FDA said it believes "that the definition of pCR proposed in this guidance has the greatest likelihood of predicting clinical benefit for regulatory purposes in patients with early-stage breast cancer who achieve pCR following neoadjuvant systemic therapy."
Reuters notes this is a significant paradigm shift from FDA's existing thinking, and will potentially allow patients to gain access to drugs much more quickly. Under FDA's current regulatory framework, patients with early stage breast cancer are unable to access breast cancer drugs until they are proven to be safe and effective in advanced-stage breast cancer.
FDA Commissioner Margaret Hamburg said the draft guidance reflects her agency's push to get innovative products to market in a safe and responsible manner. "We understand the importance of taking an advance in science as quickly as we can to the patients who need them," said Hamburg to Reuters. Hamburg added that despite the move to accelerate the approvals process, the agency is "always being mindful of our responsibility of looking at the issues of safety and efficacy."
Reuters - FDA to let women try new breast drugs earlier
Guidance for Industry - Pathologic Complete Response in Neoadjuvant Treatment of High-Risk Early-Stage Breast Cancer: Use as an Endpoint to Support Accelerated Approval
The Pink Sheet - FDA Lays Out Path For Neoadjuvant Approvals In Breast Cancer
Regulatory Focus - FDA Releases Draft Guidance for Accelerated Approval of Breast Cancer Treatments