Biotech Ionis Pharmaceuticals surges 35% after upbeat trial of triglyceride drug

Quotes of biotech Ionis Pharmaceuticals jumped 35% in a single day after it announced a successful trial of a drug that reduces triglyceride levels in the blood and prevents cases of acute pancreatitis. Analysts were positive about the results. The company, which is known for its Spinraza drug for spinal muscular atrophy, could see its shares rise another 40%, according to some analysts' models. 

Shares of mid-cap biotech Ionis Pharmaceuticals soared nearly 35% to reach a four-year high close of $57.50 per share yesterday, September 2. In premarket trading today, the stock has added 1.8% as of this writing.

The surge was driven by the positive results of the final, phase III trial of Tryngolza (olesarsen) among patients with hypertriglyceridemia, a condition in which blood triglyceride levels are elevated. It is common in the U.S.

Ionis announced yesterday that monthly Tryngolza injections lowered triglyceride levels by about 70% over six months and reduced the number of pancreatitis attacks by 85% over a year. That makes it the first such drug to seriously reduce the incidence of acute pancreatitis, the company said.

Tryngolza has already been approved by the FDA and authorized for sale in the U.S., but in limited quantities – the company sells it to only a few thousand patients, Barron’s noted. The drug is currently prescribed to adults with familial chylomicronemia syndrome, a rare genetic disorder in which the body cannot break down triglycerides, causing them to accumulate to dangerously high levels.

On a conference call yesterday, Ionis said it hopes to file an application by year end to sell it to the more than 2 million patients with severely high levels of triglycerides. A launch in the second half of 2026 will target about 1.2 million of those patients, the people at the highest risk.

RBC Capital Markets analyst Luca Issi called the results a "home run," easily beating investors' expectations. He added: "this is an absolute best-case scenario for IONS."

Approval of the drug could open a $1.7 billion market for Ionis if the company reaches just 15% of patients with severely high levels of triglycerides, calculates William Blair analyst Myles Minter. The triglyceride treatment will be the third product launched by Ionis without a big pharma partner, which strengthens Minter's conviction in his "buy" rating on the company's shares, Barron's reported.

Following the results, Oppenheimer raised its target price on Ionis from $78 per share to $81 per share, for 40% upside, while maintaining its "outperform" rating. 

Since the beginning of the year, Ionis is up more than 64%. Of the 29 analysts who cover the stock, 21 rate it either a "buy" or "overweight" versus seven "holds" and one "sell," MarketWatch points out. Their average target price of $66.40 per share offers 15% upside versus current quotes.

Ionis Pharmaceuticals has been in business since 1989 and specializes in antisense therapy, which involves turning off or stopping the synthesis of a protein involved in a disease's development. Such drugs are designed to find and destroy a specific faulty genetic instruction (an RNA molecule) before the harmful protein is even produced. They make it possible to treat the cause of a genetic disease rather than just the symptoms.

Ionis has several approved drugs, the best known and most commercially successful of which is Spinraza (nusinersen) for the treatment of spinal muscular atrophy, a severe genetic disease in which a patient gradually loses the ability to walk, move, and even breathe. In 2024, Spinraza generated sales of $1.60 billion, with royalty revenue of $216 million – 30% of the company’s total annual revenue of $705 million.

The AI translation of this story was reviewed by a human editor.