Shares of AstraZeneca fell as much as 9% after a late-stage clinical trial for a heart disease drug failed to meet its goal.

The drug Wainua did not achieve its main goal of reducing deaths and recurrent heart-related emergencies over 140 weeks compared to a placebo when it was added to a patient’s current treatment plan, the British drugmaker said in a news release early Thursday.

The treatment was for a rare, life-threatening heart disease called transthyretin-mediated amyloid cardiomyopathy (ATTR-CM).

Jefferies analysts said the result did not threaten the company’s revenue target of $80 billion by 2030, but noted that AstraZeneca was “very confident about the primary endpoint and ability to achieve when used in combination.”

“The larger issue is likely to be some loss of credibility as management is very confident that the trial can meet the primary endpoint and show benefit in addition to background therapy,” the analysts added.

AstraZeneca confirmed that its existing license for Wainua was not affected by these trial results. The drug is already approved to treat conditions in which misfolded proteins build up and cause nerve damage. It is sold in Europe as Wainzua.

This study looked at a specific type of disease in which misfolded proteins build up in the heart muscle, making it stiff, making it difficult to pump blood and eventually leading to heart failure. It is estimated that around half a million people live with this disease.

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AstraZeneca’s London-listed shares over the last 12 months.

The stock was last down 8.8% in London, on track for its worst day since March 2020 at the start of the Covid-19 outbreak. Stocks listed on the NYSE lost 8% in premarket trading.

Shares of Ionis Pharmaceuticalswhich Wainua is co-developing in the US, fell 12.5% ​​in premarket trading.

In the study cohort, the majority of patients already received a stabilizer that prevents the protein from misfolding from the outset. Since the patients were already receiving treatment for this, adding Wainua – a so-called gene silencer – in addition to standard treatment did not show any significant additional benefit for the overall group.

In patients who were not taking a stabilizer at baseline, Wainua showed a “nominally significant” risk reduction in death and cardiac events compared with placebo, AstraZeneca said.

Still, Citi analysts said it was unlikely AstraZeneca would be able to seek additional approvals for Wainua because it missed its Nasdaq-listed primary endpoint Alnylam Amvuttra already has a treatment for ATTR-CM on the market.

Shares of Alnylam Amvuttra rose 16% in pre-market trading.

“Although the study did not meet its primary objective, we believe the results support a better scientific understanding of treatment approaches for the hundreds of thousands of patients worldwide suffering from this progressive and often fatal disease,” said Sharon Barr, executive vice president of BioPharmaceuticals R&D at AstraZeneca.

The full data will be presented at the European Society of Cardiology in August.

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