What happened

Moderna is up about 9.7% at $159.77 as of 11:50am ET, having traded between $149.50 and $161.96 against Wednesday's close of $145.62. Investing.com reported it up 9.39% at $159.43 in morning trade.

Now the strange bit: there's no Moderna news today. No data, no filing, no earnings, no deal. Investing.com puts it down to momentum buying and short-squeeze dynamics. The Nasdaq rose 1.51% in the same session, so roughly eight points of this belong to Moderna alone. What the market's still chewing on happened four weeks ago.

Why it moved

On 19 August 2026, Merck and Moderna said their Phase 3 trial, INTerpath-001, met its endpoints. The drug, intismeran autogene, is a cancer vaccine built for one patient at a time: sequence that person's tumour, find the mutations unique to it, then manufacture an mRNA shot that trains their immune system to hunt cells carrying those mutations. It was tested alongside Merck's Keytruda in 1,137 patients with completely resected stage IIB–IV melanoma and no prior systemic treatment.

It hit recurrence-free survival (how long before the cancer returns) and distant metastasis-free survival (how long before it spreads) — the first personalised mRNA cancer vaccine to clear a Phase 3. BioPharma Dive reported the shares surged more than 170% and added roughly $45bn of market value on the news.

Here's what most headlines skipped: the Phase 3 numbers themselves haven't been published. Merck's release says only that the endpoints were met, with full data due at a future medical meeting and overall survival still being measured. Every figure being quoted comes from the earlier, much smaller Phase 2b trial KEYNOTE-942 — a 49% lower risk of recurrence or death (hazard ratio 0.51) and 59% lower risk of distant spread (HR 0.411). The market is pricing a result whose size nobody outside the two companies has seen.

Valuation

Moderna has no P/E — it loses money, so stockanalysis.com reports it as N/A. The trailing-twelve-month net loss is $3.15bn on revenue of $2.23bn, against a market cap of $62.79bn — roughly 28x trailing sales (our arithmetic on those two reported figures).

Closest listed peer BioNTech: market cap $24.86bn, TTM revenue $3.03bn, a $1.93bn loss, also no P/E — about 8x sales, on more revenue than Moderna. A five-year P/E range doesn't exist either, and that absence is the story: Moderna earned $12.2bn in 2021 and $8.36bn in 2022, then lost money every year since. Its 52-week range is $22.28 to $176.66.

The business

The catalyst isn't the company. Moderna's revenue comes from respiratory vaccines — COVID, RSV and flu — and that base has shrunk hard: $19.26bn in 2022 to $6.85bn in 2023, $3.24bn in 2024 and $1.94bn in 2025. Cash and investments were $6.91bn at 30 June 2026. The oncology programme driving the stock sells nothing, isn't approved anywhere, and per William Blair the melanoma economics would split roughly 50-50 with Merck. So a $62.79bn valuation rests on an unapproved, half-owned asset while the part that earns money is nine-tenths smaller than four years ago.

Who it touches

• Merck — owns half the melanoma economics and supplies Keytruda, the backbone of the combination.
• BioNTech — up only ~2.5% today despite running a rival mRNA cancer programme. Its own cancer vaccine missed its mark in August, so the market is pricing Moderna's specific asset, not the category.
• Novavax — up ~9.8% at $10.27 on no data of its own; small-cap vaccine names get dragged along.
• Analysts, openly split — William Blair models $5.4bn of peak annual melanoma sales, while Evercore ISI's Cory Kasimov says the valuation "already prices in substantially more conviction than the data disclosed thus far supports".

The rest of today's outsized moves are on the movers page.

What to watch

One risk flips this. When the full Phase 3 data is presented, the hazard ratio becomes public. If it lands meaningfully weaker than the Phase 2b 0.51 — or if overall survival, still being collected, doesn't follow — little holds the gap between a $62.79bn market cap and $2.23bn of shrinking revenue. Manufacturing is the other open question: every dose is built for one patient, and nobody has run that at commercial scale. Medical-meeting and regulatory dates land on the calendar.

As of 11:50am ET, 17 September 2026. Sources: Investing.com, BioPharma Dive, Merck press release, stockanalysis.com. For discussion and education only — not investment advice. Verify before acting.