Arrowhead's blood-brain barrier tech is 'arguably better' than others, analysts say after data drop. October 15, 2026 | Arrowhead Pharmaceuticals' siRNA candidate achieved "compelling" tau reductions in an early study of healthy volunteers, with a magnitude of effect that seems to outperform other blood-brain barrier platforms, according to Stifel. Arrowhead Pharmaceuticals' investigational gene silencer lowered tau protein levels in an early study, suggesting that the biotech's approach to bypass the blood-brain barrier may be better than competing technologies. The findings "provide important clinical validation" for Arrowhead's platform for targeting the central nervous system through subcutaneously administered drugs, Stifel analysts said in a Wednesday note. Results from the Phase 1/2a study, disclosed Wednesday, showed a 40% average reduction in CSF tau at day 105 in healthy volunteers who were treated with the low 2.1-mg/kg dose of the siRNA candidate, called ARO-MAPT, on days 1, 8 and 15. In those given a 6.4-mg/kg dose on the same days, CSF tau dropped by 69% on average at day 105. Meanwhile, a 12.8-mg/kg dose of ARO-MAPT injected on days 1 and 15 triggered a mean CSF tau reduction of 73% at day 105. The maximum CSF tau reduction reached 85% in the high-dose cohort. The early trial is actively enrolling patients, with a target of 112 participants, including healthy volunteers for the study's first part and patients with early Alzheimer's disease for the second portion. Wednesday's data came from healthy volunteers. As for safety, the primary objective of the Phase 1/2a trial, Arrowhead said that ARO-MAPT was "generally well tolerated." Treatment-emergent adverse events were largely mild, with no serious side effects, deaths or dropouts due to toxicities. The data, while early, could set Arrowhead up to compete against Biogen, analysts say. Both companies are advancing tau-targeting therapies that work by suppressing the expression of the MAPT gene, which codes for the tau protein. "While details are still relatively light, the data looking compelling," Stifel told investors in a note on Wednesday, adding that the interim findings are "arguably better than what we've seen with other BBB platforms." The firm also hinted at a potential competitive edge for Arrowhead's subcutaneous siRNA asset, writing that the CSF tau knockdown "looks better than [Biogen's] BIIB080," an anti-tau antisense oligonucleotide also known as diranersen that is injected directly into the spine. ARO-MAPT, meanwhile, can be delivered via an injection under the skin. Phase 1b data for diranersen published in 2023 showed that, across various dose levels, CSF tau declined by an average of 30% to 49% at eight weeks after the final dose of Biogen's asset. Diranersen's tau-lowering effect persisted through 24 weeks after the last dose, hitting an average tau reduction of up to 56%. The trial enrolled 46 patients with mild Alzheimer's disease, and its primary endpoint was safety; CSF tau was set as a key exploratory outcome. There have been no direct head-to-head studies between ARO-MAPT and diranersen, which prompted Jefferies to be a bit more reserved about comparing the two assets. The firm in a Wednesday note pointed to differences in study populations and dose strengths. In May, Biogen announced that diranersen failed to meet its primary goal of showing a dose-response effect in cognitive and functional outcomes in the Phase 2 CELIA study. Nevertheless, the company detected "robust reductions in tau pathology" that were consistent with the Phase 1b study. Biogen also touted cognitive improvements and slowing of decline, especially in patients who received the lowest dose of diranersen. Based on these efficacy signals, Biogen has decided to push diranersen into registrational development, though the company has yet to specify a timeline for this. Arrowhead is also moving forward with ARO-MAPT, with additional healthy volunteer and Alzheimer's disease data expected next year. Arrowhead is also in talks with health regulators to enable studies in MAPT-associated frontotemporal dementia and progressive supranuclear palsy, according to the Wednesday announcement.

Arrowhead Pharmaceuticals director sells 11,600 shares for $1 million. Perry's liquidity event comes as the Arrowhead stock price surged. By Jack Delaney - Sep 6, 2026 at 5:55PM EST Key points. * The transaction was valued at $1 million. * The sale reduced the director's direct equity holdings by 9%. * Perry maintains direct ownership of approximately 111,000 shares. * 10 stocks The Motley Fool, LLC like better than Arrowhead Pharmaceuticals" Michael S. Perry, a Director at Arrowhead Pharmaceuticals (ARWR -0.17%), sold 11,600 shares of common stock on Aug. 18, 2026, according to an SEC Form 4 filing. Transaction summary. | Metric | Value | | Transaction value | $1 million | | Shares sold | 11,600 | | Post-transaction shares (directly held) | 111,459 | | Post-transaction value | $9.8 million | Transaction value based on SEC Form 4 weighted average sale price ($87.30); post-transaction value based on Aug. 18, 2026, market close ($87.90). Key questions. * What were the specific execution details of this open-market sale? The shares were disposed of in multiple transactions at prices ranging from $87.20 to $87.44, with the reporting person providing full trade data to the company and the SEC upon request. * How does this transaction impact the insider's total stake in the company? By selling 11,600 shares, the director liquidated 9% of his direct holdings. However, he remains a stakeholder with 0.0791% of the company's equity and continues to hold common stock underlying unvested restricted stock units. * What is the current market valuation context for Arrowhead Pharmaceuticals? The Pasadena-based biotechnology company maintains a market capitalization of $12.2 billion, with shares priced at $89.41 as of the Aug. 19, 2026, market close. * What are the fundamental financial metrics for the firm? Arrowhead Pharmaceuticals reported trailing twelve-month revenue of $669.5 million and a net loss of $320 million as it continues to advance a therapeutic pipeline centered on RNA interference technology. Company overview. | Metric | Value | | Share Price (as of market close 2026-08-19) | $89.41 | | Market Capitalization | $12.6 billion | | Revenue (TTM) | $669.5 million | | Net Income (TTM) | -$320 million | Company snapshot. * Arrowhead Pharmaceuticals develops innovative biopharmaceutical treatments leveraging RNA interference (RNAi) technology, with a clinical pipeline focused on complex, challenging-to-treat diseases, and generates revenue through therapeutic development and commercialization. * The company operates as a discovery-stage to clinical-stage biopharmaceutical enterprise, advancing multiple therapeutic candidates through clinical trials to achieve regulatory approval and subsequent commercialization in the United States market. * Arrowhead targets patients with rare genetic diseases and complex liver conditions, including alpha-1 antitrypsin deficiency, positioning itself in the specialty pharmaceutical and orphan drug markets where unmet medical needs remain substantial. Arrowhead Pharmaceuticals, founded in 1989 and headquartered in Pasadena, California, represents a clinical-stage biopharmaceutical company with a market capitalization of $12.2 billion and 711 employees. The company's strategic focus on RNAi-based therapeutics provides a differentiated technological platform for addressing genetic and metabolic disorders with limited treatment options. With TTM revenue of $669.5 million and continued investment in its pipeline, Arrowhead demonstrates the capital-intensive nature of biopharmaceutical development. However, the company remains positioned to capture significant value upon successful advancement and commercialization of its clinical candidates. Arrowhead Pharmaceuticals Premium Feature Moneyball Superscore Today's Change ( -0.17 %) $ -0.15 Current Price Key data points. Market Cap Day's Range $ 84.20 - $ 86.96 52wk Range $ 27.10 - $ 95.49 Gross Margin What this transaction means for investors. Over the last 12 months, the Arrowhead stock price has skyrocketed 217.7%. In comparison, over the same period, the S&P 500 has climbed 18.8%. With that context and the amount of shares sold, this appears to be a routine transaction from Perry. While he did sell 11,600 shares, he still directly holds 111,459 shares, signaling continued confidence in the company. The sale is likely just Perry taking some profits off the table, and not something shareholders should read too much into. For what's ahead for the company, analysts are bullish, but shareholders may still want to keep their expectations in check. With the stock already climbing over 217.7% over the past year, it will be difficult to keep that pace. According to CNN, all 14 who cover the stock rate it a buy. Among those analysts, the median one-year price target is $109.50, representing a 26.8% gain from the current price of $86.34. The highest price target, $126, would represent a gain of nearly 46%. The lowest price target, $100, still would represent a gain of 15.8%. Should you buy stock in Arrowhead Pharmaceuticals right now? Before you buy stock in Arrowhead Pharmaceuticals, consider this: The Motley Fool Stock Advisor analyst team just identified what they believe are the 10 best stocks for investors to buy now... and Arrowhead Pharmaceuticals wasn't one of them. The 10 stocks that made the cut could produce monster returns in the coming years. Consider when Netflix made this list on December 17, 2004... if you invested $1,000 at the time of its recommendation, you'd have $421,997!* Or when Nvidia made this list on April 15, 2005... if you invested $1,000 at the time of its recommendation, you'd have $1,413,876!* Now, it's worth noting Stock Advisor's total average return is 978% - a market-crushing outperformance compared to 213% for the S&P 500. 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Arrowhead Pharmaceuticals reported positive Phase III results for plozasiran in severe hypertriglyceridemia, showing triglyceride reductions of 79% to 81% and a 78% decrease in acute pancreatitis events versus placebo. The company plans to submit a supplemental FDA application before the end of 2026. The firm's REDEMPLO therapy for familial chylomicronemia syndrome is gaining traction, with prescription volume more than doubling and quarterly revenue reaching approximately $2.4 million. Over 400 prescribers are now supported. For the fiscal third quarter ended 30 June 2026, Arrowhead recorded revenue of approximately $75 million, up from $28 million year-on-year. Net loss widened to $194.3 million from $175.2 million. The company held about $1.6 billion in cash and investments.