NEW YORK, July 9, 2026, 15:02 (EDT)
- Ionis shares fell 23.2% late after Wainua failed to meet the primary endpoint in a big heart-disease trial.
- The drop was steeper than the rest of biotech, as XBI and IBB traded up.
- The setback puts investors’ eyes back on Ionis’ launches like TRYNGOLZA, taking attention off a bigger Wainua cardiomyopathy push.
Ionis Pharmaceuticals NASDAQ:IONS dropped about $3.2 billion in market cap Thursday after its partner AstraZeneca’s (LON:AZN; NASDAQ:AZN) heart drug Wainua missed the primary endpoint in a key late-stage trial. Shares of Ionis traded at $64.83, off 23.2%, as of 2:46 p.m. ET. By then, the SPDR S&P Biotech ETF (NYSEARCA:XBI) was up 0.7%, and iShares Nasdaq Biotechnology ETF (NASDAQ:IBB) gained 0.2%.
The gap drove the move. This wasn’t a sector move. It was about resetting expectations over whether Wainua might leap from a niche nerve-disease market into ATTR-CM, also known as transthyretin-mediated amyloid cardiomyopathy, a serious heart disease where misfolded transthyretin protein piles up in the heart and makes pumping blood tougher.
Ionis and AstraZeneca reported the CARDIO-TTRansform Phase 3 trial did not hit its primary endpoint. The main measure, which was a combo of cardiovascular death and recurrent events tracked for 140 weeks, fell short. Patients who were already on stabilizer drugs didn’t show benefit from the treatment. In a monotherapy subgroup, the hazard ratio came in at 0.71, so treated patients looked better than placebo, but the result was only nominally significant and didn’t change the overall outcome.
| Latest market snapshot | Price | Day move | What it says |
|---|---|---|---|
| Ionis NASDAQ:IONS | $64.83 | -23.2% | Cardiomyopathy option value slashed by investors |
| AstraZeneca ADR NASDAQ:AZN | $178.80 | -5.5% | Big partner took a hit too, just not as steep |
| BridgeBio Pharma NASDAQ:BBIO | $91.94 | +17.4% | ATTR-CM exposure lifted the rival |
| Alnylam Pharmaceuticals NASDAQ:ALNY | $322.55 | -0.3% | Early pop on read-throughs faded by the close |
| Pfizer NYSE:PFE | $24.19 | +0.6% | Stabilizer line seen as holding up better than expected |
BofA’s Sachin Jain told Reuters the data “comes as a surprise.” JM Finn’s Lucy Coutts said the result could keep expectations for AstraZeneca in check. Reuters said analysts had looked for as much as $2 billion in peak sales for Wainua in this heart disease use. Reuters
The competitive angle is limited but matters. Wainua and Alnylam’s Amvuttra both lower transthyretin protein, while Pfizer’s Vyndaqel works by stabilizing protein already in the blood. BridgeBio also offers an approved ATTR-CM drug. With this trial not showing a benefit when added to stabilizer drugs, payers may ask why they should cover a combination if the added benefit is uncertain.
Jefferies dropped its Ionis target to $90 from $113 but stuck with a Buy call. Analyst Akash Tewari said the trial shortfall probably came from tafamidis “over performance,” referring to Pfizer’s stabilizer. TD Cowen moved its target to $94 from $108, kept its Buy rating, and said the Wainua monotherapy result looked in line with Amvuttra’s HELIOS-B data. Investing.com
| Analyst reset after the miss | New target | Prior target | Rating kept | Main read-through |
|---|---|---|---|---|
| Jefferies | $90 | $113 | Buy | ATTR-CM combo studies now more difficult |
| TD Cowen | $94 | $108 | Buy | Monotherapy still looks solid vs. combo add-on |
| Oppenheimer | $92 | $110 | Outperform | Miss narrows near-term gains, pipeline still in play |
The valuation impact is bigger than the effect on near-term royalty revenue. Wainua pulled in $51 million in global Q1 sales for AstraZeneca and led to $11 million in royalty revenue for Ionis. Ionis reported total Q1 revenue of $246 million. Cash and short-term investments were at $1.9 billion as of March 31. In April, the company raised its 2026 revenue outlook to $875 million-$900 million.
Ionis CEO Brett Monia called the miss part of a “rapidly evolving treatment landscape” and said Ionis will keep its focus on its fully owned pipeline. Primary investigator Mathew Maurer from Columbia University said the results offer “important clarity” for the sector, but full data isn’t out until the European Society of Cardiology Congress in August. Ionis Pharmaceuticals, Inc.
That puts TRYNGOLZA back at the center of the story for the stock. The U.S. Food and Drug Administration approved TRYNGOLZA on June 24 for reducing triglycerides and lowering risk of acute pancreatitis in adults with severe hypertriglyceridemia. It’s Ionis’ first independent commercial launch in a common disease. Ionis said the drug should be available in the U.S. in July.
The downside risk is still open. If regulators think the monotherapy subgroup is too small, or if payers see little use for Wainua outside of stabilizers, the cardiomyopathy push could get delayed or even wiped out. Ionis would then have to fall back on TRYNGOLZA sales, DAWNZERA growth, and other pipeline prospects to support a stock that’s still priced on upcoming launches, not profits now, even after Thursday’s drop.
