Nektar Therapeutics’ experimental breast cancer drug, and key to the company’s future growth, failed a late-stage study.
The company said that its NKTR-102 failed to meet its primary endpoint in the Phase III BEACON study. The drug is considered key to the Nektar’s future growth. The company’s CEO Howard Robin had previously mentioned new blueprints for a big expansion for new staff that would assist in commercializing the breast cancer drug.
The late-stage study evaluated single-agent NKTR-102 in patients with advanced breast cancer compared to an active control arm comprised of a single chemotherapy agent of physician’s choice (TPC) in patients who were heavily pre-treated with a median of three prior therapies for metastatic disease. In the 852 patient trial, NKTR-102 provided a 2.1 month improvement in median overall survival (OS) over TPC, however the effect was not considered statistically significant. Additionally, the company said that secondary endpoints, including objective response rate (ORR) and progression-free survival (PFS), did not achieve statistical significance.
The news caused the company’s stock to fall 16 percent.
Although the trial failed to meet its goals, the company found some good news, saying that the drug improved OS in a pre-specified subgroup of patients with a history of brain metastases, with a median improvement of 5.2 months.
“In BEACON, NKTR-102 provided a clinically meaningful benefit with a greater than two month survival advantage in these late-stage breast cancer patients, many who were refractory to existing therapies,” said co-principal investigator of the study Dr. Javier Cortes, Director of the Breast Cancer Program at Vall d’Hebron University Hospital in Spain. “NKTR-102 exhibited a lower rate of high grade adverse events including a reduced rate of neutropenia as compared to active control, which dramatically decreased the need for growth factor support in the NKTR-102 arm of the study. Of particular significance, median survival in patients with brain metastases was more than double on NKTR-102 and the 12-month survival rate for this sub-group was impressive at 44% compared to 19% with other active agents.”
The drug was designed to be the first topoisomerase I inhibitor with a novel molecular structure that concentrates the drug in vascularized tumors and extends its circulation time in plasma. The US Food and Drug Administration (FDA) granted the drug Fast Track designation in 2012 for treatment of patients with locally recurrent or metastatic breast cancer progressing after treatment with anthracycline, taxane and capecitabine (ATC).
“It is clear from our BEACON study that NKTR-102 has potential as an important anti-cancer agent when compared to the best available treatment options today for women with advanced breast cancer,” said Howard Robin, president and chief executive officer of Nektar Therapeutics. “Given the significant need for new drugs to treat patients with this devastating disease, we will be exploring potential paths forward for NKTR-102 in metastatic breast cancer with regulatory agencies.”
Source: Nektar Therapeutics
Last updated: 3/18/15; 11:10am EST