Moderna Stock Plunges 25%—Wiping Out $18 Billion After Historic Cancer Vaccine Breakthrough

Moderna and Merck announced positive results from a cancer vaccine trial, causing the company's stock to more than double. However, investors later sold off their shares, erasing some of those gains and reducing the company's value by billions of dollars.

7 across the spectrum. Choose a side on the bar to jump to it.

National story. 7 articles from 7 sources. Updated Aug 21, 2026.

How each side is putting it

Left

2 sources
CheddarLean Left· Aug 21, 2026

Moderna’s Cancer Vaccine Breakthrough Sends Stocks Soaring

Philadelphia InquirerLean Left· Aug 20, 2026

From COVID to cancer: How Moderna’s stock jumped 177% in a day

Center

2 sources
ForbesCenter· Aug 20, 2026

Moderna Stock Plunges 25%—Wiping Out $18 Billion After Historic Cancer Vaccine Breakthrough

Inc.Center· Aug 20, 2026

Why Moderna Stock Just Had Its Best Day Ever

Right

3 sources
The Daily CallerRight· Aug 19, 2026

Moderna Stock Skyrockets Over 100%

Ran by 2 outlets· Independent Journal Review, BizPac Review
Independent Journal ReviewRight· Aug 19, 2026

Pharma Stock Skyrockets Over 100%

BizPac ReviewRight· Aug 19, 2026

Pharma stock skyrockets over 100%

The story so far

2 developments
  1. Aug 19Only right-leaning coverage:Pharma stock skyrockets over 100%
  2. Aug 20Moderna Stock Plunges 25%—Wiping Out $18 Billion After Historic Cancer Vaccine Breakthrough

Who covered each development

No new developments

Quiet for 58 days

Last development · Aug 20 — Moderna Stock Plunges 25%—Wiping Out $18 Billion After Historic Cancer Vaccine Breakthrough

The bigger story

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You are hereAug 19, 2026

Moderna Stock Plunges 25%—Wiping Out $18 Billion After Historic Cancer Vaccine Breakthrough

2 developments · 7 sources