
Delays hit Sanofi
The Ameera-3 readout gets pushed back again, while fitusiran’s filing will not happen until 2024.

Sanofi’s efforts to rebrands itself as an oncology and rare disease powerhouse have taken a hit recently, with some of its deals failing to deliver. Now the group is contending with delays to important pipeline projects, it revealed during its third-quarter results today.
Key among these is the selective oestrogen degrader amcenestrant; readout of its pivotal Ameera-3 study, originally expected in the second quarter of this year, has already been postponed several times, and investors might now have to wait until early 2022 for the data.
Sanofi execs said during a conference call today that 90% of events in this trial had now accumulated, but the competition has already started catching up.
Interestingly, the delay means that Sanofi will be able to analyse full data from the Emerald trial of Radius/Menarini’s rival, elacestrant, which are due at December’s San Antonio Breast Cancer Symposium, before Ameera-3 reads out, and has the option to tinker with its study's statistical plan accordingly.
Fitusiran filing further away
Meanwhile, a filing for the haemophilia project fitusiran has been pushed back by two years as Sanofi investigates a lower dose in phase 3. This will do nothing to assuage worries about toxicity, which have loomed since a patient in a clinical trial died from a thrombotic event in 2017. Another clinical hold hit late last year, but was quickly lifted.
Submissions for several other novel projects are also now set to take place later than previously expected, including that for rilzabrutinib in immune thrombocytopenia. Hopes for the Principia-originated oral BTK inhibitor cannot be high after its recent failure in the skin disorder pemphigus. Sanofi executives' excuses for rilzabrutinib’s pemphigus flop included that all patients were on background glucocorticoids.
Still waiting… notable delays to novel Sanofi projects announced in Q3 2021 | ||||
---|---|---|---|---|
Project | Description/setting | Event | New timing | 2026e sales ($m) |
Amcenestrant | Serd in breast cancer | Readout of pivotal Ameera-3 trial | Q4 2021/Q1 2022 (from Q4 2021, originally expected Q2 2021) | 679 |
Fitusiran* | Anti-thrombin RNAi in haemophilia A/B | Filing | 2024 (from 2022) | 483 |
Rilzabrutinib (PRN1008) | BTK inhibitor in immune thrombocytopenia | Filing | 2024 (from 2023) | 421 |
Venglustat (GZ402671) | Glucosylceramide synthase inhibitor in Gaucher type 3 | Filing | 2024 (from 2023) | 128 |
Tusamitamab (SAR408701) | Anti-CEACAM5 MAb in 2/3L NSCLC | Filing | 2023 (from 2022) | 98 |
*Licensed from Alnylam. Source: Evaluate Pharma & company presentations. |
The setback was a black mark against Sanofi’s deal-making nous, as the French group had paid $3.7bn for Principia despite question marks about the target’s projects. It is worth noting that the main focus of the buyout, tolebrutinib, is still in play, with phase 3 trials ongoing in multiple sclerosis and a filing slated for 2024.
This is more than can be said for SP0254 (MRT5500), the mRNA Covid-19 vaccine candidate that Sanofi picked up with the $3.2bn acquisition of Translate Bio. Not long after, Sanofi said it would not pursue this vaccine, which uses unmodified mRNA, and would instead focus on modified mRNA vaccines for other diseases such as flu.
The company is not out of the Covid chase, however. It is still developing a recombinant protein-based Covid-19 jab, SP0253, which uses an adjuvant developed by Glaxosmithkline. Data from two phase 3s – concerning the efficacy of a monovalent primary vaccine and a booster jab – are set to yield data this quarter, setting up a possible request for emergency use authorisation this year.
Still, this represents a big delay to a shot that had originally been expected to hit the market this year. The slip-ups in development not only look embarrassing for a big vaccine player, but in the developed world the shot will be relegated to use as a booster, if it gets the nod at all.
Perhaps the latest pipeline update only serves as a reminder that Sanofi will have its work cut out replacing the Regeneron-partnered juggernaut Dupixent. Sales of that drug beat expectations in the third quarter, and various label expansions are planned. However, one effort, in COPD, has seen filing delayed from 2023 to 2024.
Sanofi has been trying to turn its fortunes around with a series of deals, spending nearly $13bn on bolt-ons since December 2019. But it also needs to execute, and the latest delays will have not increased confidence that the group’s overhaul will bear fruit.
This story has been updated to clarify that SP0254 was also known as MRT5500.