Merck and AbbVie are sitting at the center of a bipartisan congressional investigation, and the question being asked is pointed: did two of America's largest drugmakers help build China's military biotech capability while running human drug trials on Chinese soil?

The House China Select Committee sent letters to both companies on Monday, demanding answers by July 17. The letters, first reported by Reuters, were led by Republican Representative John Moolenaar of Michigan and include members from both parties. They are not accusing either company of breaking the law. The letters say explicitly that "there is no evidence" of illegal activity or wrongdoing. But the committee argues that the trials created real risks, and that those risks are no longer theoretical.

What the numbers look like

Merck, based in New Jersey, has sponsored or collaborated on 224 clinical studies in China since 2005. At least 31 of those were in Xinjiang. Forty more were at hospitals affiliated with China's military.

AbbVie, based in Illinois, has sponsored or collaborated on more than 100 studies in China since 2007, including 17 sites in Xinjiang and 16 at military-linked centers.

The committee's concern is that running cutting-edge drug research inside Chinese military hospitals puts American intellectual property within reach of the Chinese military, whether or not any company intended that outcome.

Why this is happening now

The investigation reflects a shift that has been building for years. In 2015, the United States ran nearly half of all early-stage global drug trials. By 2024, that share had fallen to 37 percent. China's share over the same period climbed from 8 percent to more than 32 percent. China got there through a combination of regulatory speed, state subsidies, and, according to the letters, ethics standards that researchers have documented as inconsistent, particularly around whether trial participants genuinely consented to take part.

The Xinjiang dimension sharpens the ethical edge considerably. The committee's letters describe Xinjiang as the center of Beijing's campaign of repression against Uyghurs and other minorities. The 2021 Uyghur Forced Labor Prevention Act does not specifically cover clinical trials, but the committee argues its principles should apply.

China's embassy dismissed the investigation, saying there is "nothing credible" in the committee's actions and that it opposes efforts to politicize trade and technology issues.

What it means beyond the two companies

The investigation fits inside a broader legislative push. Representative Moolenaar is also sponsoring a bill that would require American biotechnology licensing deals, joint ventures, and equity investments in China to go through a formal national security review, similar to the screening that already applies to semiconductors and other sensitive technologies.

The National Security Commission on Emerging Biotechnology warned last December that China has built "a vertically integrated biotechnology ecosystem" designed to challenge American leadership in the field. That framing, an entire industry treated as a strategic asset rather than a commercial one, is increasingly the lens through which Washington is looking at pharmaceuticals.

For ordinary Americans, this matters in two directions. The immediate one is drug development itself. If Congress moves to restrict or scrutinize where trials can run, that could slow the pipeline for new medicines or raise costs, since China became attractive in part because it is faster and cheaper. The longer-term concern is strategic: the drugs that get discovered in joint trials, and the biological data generated along the way, are increasingly understood as assets with national security value, not just commercial ones.

The deadline for Merck and AbbVie to respond is July 17. Whatever they say will land in a Congress that has already decided this industry deserves the same level of scrutiny it has applied to chips, telecoms, and artificial intelligence.