Texas Attorney General Ken Paxton is ramping up his war on big pharma with fresh allegations against two major drugmakers. This week, he filed suit against Sanofi SA (SNY) and Bristol-Myers Squibb Co (BMY), accusing them of hiding crucial information about who can actually benefit from their blockbuster blood thinner Plavix.

Here's the problem according to Texas: Plavix—sold generically as clopidogrel bisulfate—was promoted as an effective way to prevent heart attacks, strokes, and blood clots. But the state alleges the companies knew the drug works poorly or doesn't work at all for a substantial portion of patients, particularly those in Black, East Asian, and Pacific Islander communities.

The lawsuit argues that by not disclosing this information, Sanofi and Bristol-Myers Squibb misled doctors and patients into prescribing and taking a medication that was essentially ineffective for many people who needed it. Texas is invoking the Texas Health Care Program Fraud Prevention Act and consumer protection laws in its complaint.

State prosecutors claim the pharmaceutical giants raked in billions of dollars by marketing Plavix as broadly effective while sitting on data that showed serious performance gaps across certain populations. Paxton framed it as a case of profits over patient safety—companies choosing revenue over transparency about who their drug actually helps.

The timing is notable. Just one day before announcing the Plavix lawsuit, Paxton finalized a $41.5 million settlement with Pfizer Inc. (PFE) and Tris Pharma over a completely different set of allegations. That case involved claims that the companies supplied adulterated medications to children enrolled in Medicaid.

The settlement centered on Quillivant XR, an ADHD treatment that Texas officials say repeatedly failed quality-control testing. In a lawsuit filed back in November 2023, Paxton accused Pfizer and Tris Pharma of manipulating testing procedures to hide manufacturing problems between 2012 and 2018. The alleged goal: keep selling the drug and continue collecting Medicaid reimbursements despite known quality issues.

It's a one-two punch that signals Texas isn't backing down from confronting pharmaceutical companies over alleged misconduct, whether it involves concealing drug effectiveness data or cutting corners on quality control for children's medications.