Here's a classic biotech drama: a small company hits it big with clinical data, its stock goes to the moon, and suddenly everyone with a big pharma checkbook wants to be its new best friend. The latest act features French biotech Abivax SA (ABVX), which saw its shares jump roughly 1,600% in 2025. Now, the suitors are lining up.

Currently, AstraZeneca Plc (AZN) is in the pole position. According to reports, the British-Swedish drugmaker has held exclusive access to Abivax's confidential data room since early February. This isn't a casual browse—it's a formal exclusivity period that runs through March 23. Think of it as a first-date option to buy the company: AstraZeneca gets to look under the hood, crunch the numbers, and decide if it wants to make a formal acquisition offer before anyone else can.

If they don't submit a bid by that deadline, the exclusivity expires. And that's when the door reopens for other interested parties. One name waiting in the wings? Eli Lilly and Co (LLY), which has previously expressed interest in the French biotech. So, we have a ticking clock and a potential bidding war waiting to happen.

So, what's all the fuss about? Abivax, founded in 2013, is focused on inflammatory diseases. Its lead drug candidate, oral obefazimod (ABX464), is for ulcerative colitis. In July 2025, the company announced overwhelmingly positive results from its Phase 3 induction trials. The data was so strong it sent the stock into the stratosphere, pushing its market value to about 7.7 billion euros (around $8.9 billion). The therapy is still in Phase 3 trials, with a potential commercial launch eyed for 2027. Notably, the U.S. is expected to represent nearly 70% of the drug's commercial opportunity, making FDA approval a critical hurdle.

But there's another date on the calendar that could shape any deal: late June. That's when Abivax is scheduled to release additional Phase 3 maintenance trial data. This data will show how the drug stacks up against existing treatments over a longer period. It's a big deal. Potential acquirers might prefer to see these results before signing a multi-billion dollar check. Waiting could provide more certainty, but it also risks the price going up even more if the data is good—or lets a competitor swoop in.

Complicating matters is the watchful eye of the French government. The country's finance ministry has warned that any takeover of a strategic healthcare company would trigger foreign investment scrutiny. This is where AstraZeneca might have a subtle advantage. As a European company (born from a British-Swedish merger), its bid might face less political resistance than one from a U.S. giant like Eli Lilly. AstraZeneca's CEO, Pascal Soriot, who is French-Australian, also has an established relationship with Abivax CEO Marc de Garidel. They've done deals before, like AstraZeneca's 2023 acquisition of CinCor Pharma from Garidel.

For now, the ball is in AstraZeneca's court until March 23. If they pass, Eli Lilly gets a shot. And everyone will be watching the clock—both the one on the exclusivity period and the one counting down to the June data. In the meantime, Abivax stock was up over 14% in premarket trading Thursday, showing that investors are very much enjoying the show.