Biogen (NASDAQ: BIIB) has had a rough few years. Its multiple sclerosis franchise has been losing market share to generics and biosimilars, revenue has been trending downward, and the stock spent much of 2025 trading near multi-year lows.
So when Goldman Sachs raises its price target to $250, it’s worth asking what the bank is really looking at.
The short answer: Leqembi, Biogen’s treatment for Alzheimer’s, is working. And the argument for the stock goes beyond today’s sales figures, and depends on what the next 18 months could look like if several catalysts arrive in time.
Goldman analyst Salveen Richter raised the bank’s price target for BIIB from $238 to $250keeping the buy rating intact, according to MarketScreener.
The move followed a first-quarter 2026 earnings report that handily beat expectations, capped by encouraging signs from Biogen’s experimental next-generation Alzheimer’s drug.
Goldman’s $250 target reflects more than one drug working well
Goldman did not set his goal based on blind optimism. Biogen’s Q1 2026 earnings report gave the bank real data to work with.
Biogen reported first-quarter revenue of $2.48 billion, up 2% year-over-year, and non-GAAP earnings per share of $3.57, well above the consensus estimate of $2.95.
According to the Q1 2026 earnings transcript, Leqembi generated $168 million in global sales in the market during the quarter, an increase of 74% from the same period last year.
That 74% growth rate is the kind of number that gets a bank’s attention. Leqembi is still in the early stages of its business ramp, meaning the growth curve has room to deepen if some structural hurdles are overcome.
Goldman’s Salveen Richter pressed management on the first-quarter earnings call on the adoption of blood biomarkers, a key factor in determining whether Leqembi can reach more patients faster.
The short version: Adoption is accelerating, particularly through Biogen’s primary care pilot program, which is showing higher rates of biomarker use among enrolled physicians.
This is important because diagnosing Alzheimer’s in earlier stages opens up a larger pool of patients eligible for treatment.
Leqembi, Biogen’s Alzheimer’s drug, is reshaping Wall Street’s outlook for the Cambridge-based biotech’s long-term growth story. Boston Globe photo from Getty Images
What Leqembi’s business momentum really indicates
Leqembi is a FDA-approved therapy for early Alzheimer’s disease which works by removing amyloid plaques from the brain, Reuters noted.
Amyloid is a protein that accumulates abnormally in Alzheimer’s patients and is widely believed to contribute to cognitive decline.
Leqembi has between 65% and 70% market share in terms of number of patients, compared to Eli Lilly’s competing drug Kisunla, according to Eisai’s latest forecasts, Investing.com confirmed.
This is a significant advantage in a market that is still small but expected to grow substantially as awareness, diagnosis and reimbursement infrastructure improve.
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A key near-term catalyst for Leqembi’s growth, Practical Neurology confirms, is the FDA’s August 24 PDUFA decision date for IQLIK, a subcutaneous (autoinjector under the skin) formulation of Leqembi. This is important for a practical reason.
Currently, patients receive Leqembi intravenously in a clinic, every two weeks.
The subcutaneous version would allow home administration once a week in approximately 15 seconds. Patient convenience alone could significantly improve retention and access, especially in markets where infusion centers are not widely available.
Here’s what Biogen’s Leqembi growth story hinges on:
FDA approval of the subcutaneous induction formulation of IQLIK before the PDUFA date of August 24
Complete Medicare Part D Coverage coming into action from January 2027which would eliminate the biggest cost barrier for US seniors.
Continuous expansion of blood biomarker tests, allowing primary care physicians to evaluate patients earlier and more easily
International approvals in Japan and China for the subcutaneous formulation, which would add a second leg of growth outside the US.
The experimental drug that quietly added fuel to Goldman’s call
In addition to its first-quarter earnings, Biogen released another major piece of news that drew less attention than it deserved.
On May 14, 2026, Biogen’s investor relations page shared key results from the Phase 2 CELIA study for diranersen (BIIB080), an experimental drug designed to reduce tau protein in the brain.
Unlike Leqembi, which targets amyloid, diranersen goes after tau, a second protein associated with the progression of Alzheimer’s.
Biogen described the CELIA results as “the first study to show a reduction in tau pathology and a cognitive benefit in patients with early Alzheimer’s disease.”
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The trial did not meet its primary dose-response endpoint, which is a specific statistical hurdle, but Biogen revealed that it plans to advance diranersen into registration development anyway, based on the broader signals the trial produced.
Ionis Pharmaceuticals, which developed the drug and licensed it to Biogen, separately confirmed that decision.
This is significant context for Goldman’s target increase.
If diranersen wins approval in the coming years, Biogen would have two distinct mechanisms targeting Alzheimer’s, potentially giving it the deepest clinical footprint in a disease category that affects more than 6 million Americans, according to the Alzheimer’s Association.
How the BIIB has performed compared to the broader market
It helps put the stock’s recent trajectory into concrete terms. Here’s a look at the BIIB versus the S&P 500’s recent performance outlook.
The stock’s 52-week rise from $119 to nearly $206 reflects a substantial rerating, with most of the gains coming as Leqembi’s trading performance improved and several analysts raised price targets.
However, even at current levels, Biogen trades with a forward price-to-earnings ratio that remains well below its large-cap biotech peers.
UBS, which upgraded BIIB to buy with a target of $225 by the end of April 2026, according to 24/7 Wall St, noted that shares trade at about 13 times forward earnings, a significant discount for the sector. Guggenheim has a $260 price target on BIIB, also with a Buy rating, StreetInsider reported.
That gives investors a rough range of where the bullish scenario lies: somewhere between Goldman’s $250 and Guggenheim’s $260, depending on how the pipeline plays out.
What still needs to happen before BIIB can reach $250?
Goldman’s target of $250 is not a given. There are real conditions that must be met.
Risks worth keeping in mind:
Biogen Total Revenue It is still expected to decline by a mid-single-digit percentage in 2026, driven by continued erosion of its older multiple sclerosis drugs.
The company cut its Non-GAAP EPS Guidance for Full Year 2026 to $14.25 to $15.25, partly due to acquisition charges, including the planned $5.6 billion deal to buy Apellis Pharmaceuticals.
The FDA decision on IQLIK August 24 is binary. An approval would likely push the stock higher; a setback or a full response letter could quickly reverse recent gains.
Diranersen’s path from Phase 2 to approval is long, probably several years, and Phase 3 trials regularly fail, even when Phase 2 data look promising.
The Apellis acquisition deserves attention here.
Biogen reached a deal to buy Apellis for approximately $5.6 billion, adding two approved drugs in immunology and rare kidney diseases (Empaveli and Syfovre) and strengthening the case for felzartamab, its Phase 3 candidate for kidney disease.
That deal will add leverage and pressure-free cash flow in the near term, and management forecasts full debt repayment by the end of 2027.
Key Takeaways for Investors on Biogen Stock
Goldman Sachs’ $250 target reflects real business momentum: Leqembi grows 74% year over year, market leadership over Eli Lilly’s Kisunla and a next-generation drug producing the first clinical evidence of tau reduction and cognitive benefit.
The bearish case is equally real. Overall revenue continues to decline, the Apellis acquisition burdens the balance sheet and the MS franchise continues to shrink, notes Grandview Research.
The question for investors is whether Leqembi’s growth curve becomes big and fast enough to carry the weight.
The $250 target implies roughly a 15-20% upside from recent trading levels, but achieving it requires Leqembi’s momentum to sustain, IQLIK clearing its August 24 FDA hurdle, and the Alzheimer’s market continuing to expand.
Long-term investors who believe in that trajectory will find Biogen’s current valuation compelling.
Those who need more stable fundamentals may want to wait for IQLIK’s decision before adding exposure.
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This story was originally published by TheStreet on May 17, 2026, where it first appeared in the Investments section. Add TheStreet as a preferred source by clicking here.
