Argenx steps back from subcutaneous Vyvgart
A measure of the importance to Argenx of Vyvgart in immune thrombocytopenia is that the company hasn’t been put off by its comprehensive failure in a pivotal trial last November. However, it’s now accepted that subcutaneous isn’t the way to go, and has switched back to IV Vyvgart in the new phase 3. This is despite earlier insisting that the failure of the Advance-SC trial wasn’t down to that study testing a SC version, and instead blaming a high placebo response. Perhaps Argenx has been emboldened by Japan, where IV Vyvgart is approved on the basis of one study, and where the group has seen “early positive indicators of ITP launch”. In the US, however, two trials are needed, and the new study is to supplement the earlier win in the (IV) Advance study. Argenx yesterday said the new phase 3 would be about half the size of the earlier tests, use “alternative” primary endpoints, and start by the end of this year. It’s not clear whether the group has entirely thrown the towel in on SC Vyvgart in ITP; investors have to hope that it hasn’t cut too many corners in its quest for a fast approval.
Pivotal Vyvgart trials in immune thrombocytopenia
Trial | Formulation | Primary endpoint | Result |
---|---|---|---|
Advance | IV | Sustained platelet count response, defined as platelet counts of ≥50x109/l on at least four of the six visits between week 19 and week 24 | Success (22%, vs 5% for placebo) |
Advance-SC | SC | Fail (14%, vs 16% for placebo) | |
TBC | IV | TBC | Starts by end of 2024 |
Source: OncologyPipeline.
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