Over a year after rejection, Immunomedics emerges with potential blockbuster approval
A turbulent 16 months for Immunomedics has ended in a potential blockbuster approval, as the FDA granted an accelerated OK for their drug to treat an aggressive form of breast cancer.
The drug, branded as Trodelvy, is approved for metastatic triple negative breast cancer — breast cancers that lack the oncogenes that targeted therapies go after and that have helped make the disease treatable for some patients. The drug, which had breakthrough status and priority review, showed a 33% response and median duration of response of 7.7 months in 108 patients enrolled in their Phase II trial. Peak sales estimates can range as high as around $3 billion.
The approval comes over a month in advance of the company’s June 2 PDUFA date, continuing the agency’s trend of quickly approving cancer drugs they deem effective.
A little over a year ago, the FDA surprised both the company and investors by rejecting the drug. Although Immunomedics $IMMU said the concern had only been with quality controls over the facility where the drug is produced, the rejection of the biotech’s main asset shaved $1 billion off the company’s market cap. Not long after, an FDA inspection document raised concerns of a data breach at one of the company’s facilities. The CEO and CSO both later exited, and chairman Behzad Aghazadeh stepped in to run the company.
The drug, known chemically as sacituzumab govitecan, is the company’s first approval in their 37-year history. An antibody-drug conjugate, it consists of a tumor-targeting antibody attached to a cell-killing small molecule. The tumor engulfs the conjugate and the molecule kills the cancer cells. The idea first emerged in the early 2000s before petering out, but has gained traction again in recent years, most notably with the recent approvals of Seattle Genetics’ Adcetris and Padcev.
Seattle Genetics nearly acquired the Immunomedics drug in 2016. They agreed to an up-to $2 billion deal worth $300 million before venBio, which owned a 9.9% stake in the company, led a campaign against the deal, with then-managing parter Aghazadeh accusing the company’s leadership of trying to enrich themselves. The husband-and-wife team who then ran the company as CSO and CEO resigned, and Aghazadeh later organized a $250 million royalty deal to fund the company’s work.
An accelerated approval is conditional on the company conducting a follow-up study. That trial, though, has already been stopped, with an independent review board telling Immunomedics early this month their drug had already shown enough compelling efficacy. On the same day of the trial news, the company also announced that Novartis Oncology vet Harout Semerjian had been named as the new CEO.
Committee chair and Fred Hutch researcher Julie Gralow called the results of the Phase III trial “remarkable.” The comment led Cowen’s Phil Nadeau to write, “There is little question that sacituzumab will soon become standard of care in the treatment of relapsed and refractory mTNBC.”