Shares in Immunomedics have gone into steep decline after the FDA rejected its breast cancer drug sacituzumab govitecan.
The US regulator said in its rejection letter on Friday that it wants more information on the manufacturing elements in the marketing application for the antibody-drug conjugate (ADC), delaying the review of the drug for patients with advanced triple-negative breast cancer (TNBC) who have received at least two prior therapies for the disease.
Immunomedics CEO Michael Pehl
Immunomedics’ chief executive Michael Piehl said the biotech is “going to request a meeting with the FDA as soon as possible to gain a full understanding of the agency’s requirements and timelines for approval.”
He insisted on a conference call that “no new clinical or preclinical data need to be generated” for sacituzumab govitecan, and added there would be no impact on clinical trials programmes.
That’s positive news for the company, but manufacturing issues can sometimes be tricky to resolve and the delay to the review is therefore hard to gauge. There’s no word yet on the expected timeline for resubmission of the drug to the FDA.
At the moment, it isn’t clear whether the manufacturing issues are related to Immunomedics’ manufacturing facility in Morris Plain, New Jersey, which was cited by the FDA for a number of violations – including data integrity and quality issues – after an inspection by the agency last year. The company stopped short of ruling out that link when responding to questions on the call.
Immunomedics’ management also expressed surprise at the rejection, indicating that there had been no indication from the FDA of problems with the application before the response letter was received.
Pehl told investors that the clinical data for the drug is strong and for a patient group whose options are “more than limited” so he expects there will be a speedy interaction with the FDA to try to get the programme back on track.
Sacituzumab govitecan – formerly known as IMMU-132 – is a Trop-2-targeting ADC that has breakthrough and accelerated review status from the FDA. It combines SN-38 – an active metabolite of the chemotherapy drug irinotecan – with an antibody targeting Trop2, a glycoprotein overexpressed in various solid tumours.
The drug was the subject of an investor revolt when the biotech’s former management tried to license it to Seattle Genetics in 2017, which ultimately claimed the scalps of Immunomedics’ former president and CEO Cynthia Sullivan and company founder David Goldenberg.