Category: Health

One of the most closely watched experiments in cancer medicine hit the public in the least orderly way possible on Thursday, when detailed results from a late-stage trial of Moderna’s personalised melanoma vaccine leaked online ahead of schedule — and the market’s reaction wiped around $24 billion from the company’s value.

The data, for a treatment called intismeran developed jointly by Moderna and Merck, appeared on the oncology website Oncology Central before its planned presentation at the ESMO cancer conference in Madrid on Saturday. The leak forced the conference organisers to lift their embargo, and the two companies released the full results themselves.

On the numbers, the trial was a success. More than 1,100 high-risk melanoma patients who had undergone surgery received either intismeran plus Merck’s Keytruda or Keytruda alone. The combination reduced the risk of cancer returning or of death by 42%, and cut the risk of distant metastasis or death by 38%. About 82% of patients who received the vaccine were alive without their melanoma returning at two years, compared with roughly 70% on Keytruda alone.

Dean Li, president of Merck Research Laboratories, called the study “one of the most significant advances in melanoma treatment since the advent of immunotherapy.”

Analysts agreed the science was strong. UBS’s Michael Yee described the data as “solid”; William Blair’s Myles Minter went further, calling it “great.”

The share price told a different story. Moderna stock sank as much as 25.2% to $183.88 during Thursday’s session — its steepest one-day fall on record — before closing 17.6% lower. Merck shares slipped about 1%.

The rout, described by analysts as a classic “sell-the-news” reaction, followed a months-long rally that had lifted Moderna’s stock more than 500% this year as investors piled in ahead of the trial readout. With expectations set so high, strong-but-not-miraculous data gave holders an excuse to take profits.

Overall survival data from the trial is not yet mature, though the companies said it shows a “favourable trend.” Moderna and Merck said they are engaging with regulators and plan to pursue approval. The formal presentation of the results is still scheduled for Saturday in Madrid.

Sources: Reuters (https://www.reuters.com/business/healthcare-pharmaceuticals/moderna-sheds-about-24-billion-cancer-vaccine-data-triggers-sell-the-news-2026-10-22/) and MarketWatch (https://www.marketwatch.com/story/modernas-stock-tumbles-after-reported-leak-of-data-for-cancer-vaccine-dcc897c1).

Poland has committed to join a global network of regulators overseeing the use of artificial intelligence in healthcare, becoming only the second European Union member state to do so as Europe’s new AI rules begin to bite and concerns grow about unpredictable behaviour by medical AI systems.

The agreement, announced on Thursday, is a memorandum of understanding between Poland’s Ministry of Health and HealthAI, the Geneva-based agency that runs the Global Regulatory Network (GRN). The document was drafted earlier this year at the AIMed 2026 conference in Kraków by Deputy Health Minister Tomasz Maciejewski and HealthAI’s chief executive, Dr Ricardo Baptista Leite, and it sets out a one-year cooperation framework to prepare Poland for full membership. There is no fixed timeline for accession, a HealthAI spokesperson said.

Portugal is the only other EU country in the network. Its other members include Britain, India, Brazil, Singapore, the Philippines, Indonesia, Vietnam, Zambia and Peru. Membership gives regulators access to AI healthcare tools that other regulators have already reviewed, and to a real-time warning system through which countries share reports of harmful incidents — a kind of early-warning radar for when a medical algorithm goes wrong somewhere in the world.

As part of the pathway, Poland takes a seat in the Leadership Group of HealthAI’s Community of Practice, where its officials can exchange experience with government and regulatory authorities from around 30 countries. HealthAI and the Polish health ministry will also jointly organise a meeting in Poland bringing together government, regulators, academics, clinicians and health-tech companies to build national agreement on how AI should be governed in the health system.

“Poland’s intention to join the GRN reflects a commitment to international collaboration and alignment, ensuring that innovation in AI translates into better health outcomes for Poland and for Europe,” Leite said.

The move comes as the European Union’s AI Act — the world’s first comprehensive AI law — moves into full effect, and as hospitals across Europe adopt AI tools for scanning images, triaging patients and drafting clinical notes faster than regulators can evaluate them one by one. The Polish government’s calculation is that a mid-sized country gains more influence, and safer technology, by pooling scrutiny with partners than by assessing every product alone. HealthAI, for its part, pointed to Poland’s growing health-tech sector and strong clinical research base as assets the country brings to the network.

The harder test will come later: whether shared warnings and shared reviews can keep pace with the speed at which AI products are reaching hospital wards.

Sources:
Reuters — https://www.reuters.com/business/healthcare-pharmaceuticals/poland-become-second-eu-member-global-healthcare-ai-network-2026-10-22/
HealthAI / EIN Presswire — https://lifestyle.loopbiz.com/story/426118/polands-ministry-of-health-signs-agreement-with-healthai-advancing-responsible-ai-governance-in-health-across-europe/