Sanofi hit by filing delays for key drugs, drops an early Sangamo thalassemia asset

Sanofi, in its third-quarter financials posted early Thursday morning, outlined a list of delays for a number of key assets as it dropped a biotech-partnered drug.

First up, those delays: We already knew its hemophilia hopeful fitusiran had problems after Sanofi started a new lower dose cohort in its phase 3 amid safety concerns, but now we know filing for the RNAi drug is not expected until 2024, after originally being penned in for next year.

RELATED: Sanofi revises fitusiran dosing to cut risk of thrombotic events in hemophilia phase 3

Filings have also been pushed back a year for the CEACAM5-targeted antibody-drug conjugate tusamitamab in lung cancer, which will now be into 2023, with venglustat in Gaucher disease type 3 and rilzabrutinib in the rare blood disorder immune thrombocytopenia (ITP), also both pushed into 2024.

Both these latter drugs have history: The glycosphingolipid inhibitor venglustat flopped a late-stage test in autosomal dominant polycystic kidney disease this summer, forcing the French Big Pharma to halt work on this indication, and came after a similar failure in Parkinson’s, dramatically reducing the so-called “pipeline-in-a-pill” down to Fabry disease and GM2 gangliosidosis as well as the now delayed Gaucher type 3.

BTK inhibitor rilzabrutinib, another “pipeline-in-a-pill” that came out of its $3.7 billion buyout of Principia Biopharma has also seen setbacks, falling at the first hurdle earlier this year when it missed its primary endpoint in a phase 2 for rare autoimmune skin disease pemphigus. That ITP target is still in the works but is now also notching a delayed filing date.

One of its biggest prospects, the oral selective estrogen receptor degrader (SERD) cancer hopeful amcenestrant, has also seen yet another readout pushback: At one point, the so-called AMEERA-3 trial in second-third line breast cancer was due to read out in the last quarter but is now not expected until the first quarter of 2022.

RELATED: Menarini, chased by 3 Big Pharmas, records win in breast cancer phase 3, plots path to FDA

That’s a blow for Sanofi, as one if its smaller SERD rivals, Menarini/Radius, just last week posted some positive phase 3 data from elacestrant suggesting it could boost progression-free survival, and is now plotting a path to the FDA.

And finally, Sanofi quietly announced (PDF) it was sweeping out work on its Sangamo-partnered therapy ST400, which had been in a phase 1 for the severe blood disorder transfusion-dependent beta thalassemia.

The pair are continuing work on SAR445136, formerly known as BIVV003, for sickle cell disease, but Sanofi said in its financials that: “The parties agreed to terminate the program addressing transfusion-dependent β-thalassemia (ST400) while focusing resources on the sickle cell disease indication.”