Gossamer Bio's Phase 3 Trial Results Disappoint
Written by Emily J. Thompson, Senior Investment Analyst
Updated: Feb 23 2026
0mins
Should l Buy GOSS?
Source: Benzinga
Gossamer Bio's shares fell sharply, hitting a 52-week low, following disappointing results from its Phase 3 PROSERA trial for seralutinib, which showed significant but insufficient improvement in patient mobility.
The trial revealed that seralutinib led to a median change of +28.2 meters in Six-Minute Walk Distance (6MWD) at Week 24, failing to meet the predefined efficacy threshold. However, in a subgroup of patients with connective tissue disease-associated pulmonary arterial hypertension, the drug achieved a placebo-adjusted gain of +37.0 meters, indicating potential effectiveness. Gossamer plans to meet with the U.S. FDA to discuss future development for seralutinib while pausing enrollment in the SERANATA study to evaluate the impact of these results.
The market reacted negatively, with Gossamer Bio's shares plummeting by 77.12% to $0.59, reflecting investor disappointment and prompting analysts to lower their earnings expectations.
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Analyst Views on GOSS
Wall Street analysts forecast GOSS stock price to rise
4 Analyst Rating
3 Buy
1 Hold
0 Sell
Strong Buy
Current: 0.452
Low
10.00
Averages
12.33
High
15.00
Current: 0.452
Low
10.00
Averages
12.33
High
15.00
About GOSS
Gossamer Bio, Inc. is a late-stage, clinical biopharmaceutical company, which is focused on the development and commercialization of seralutinib for the treatment of pulmonary arterial hypertension and pulmonary hypertension associated with interstitial lung disease (PH-ILD). Seralutinib, also known as GB002, is an investigational inhaled, small-molecule, platelet-derived growth factor receptor (PDGFR), colony-stimulating factor 1 receptor (CSF1R), and c-KIT inhibitor, being evaluated in a Phase III clinical trial for the treatment of PAH. Seralutinib is designed to target the mechanisms that underlie pulmonary hypertension and to be delivered to the site of disease, via dry powder inhaler. Seralutinib is being evaluated in a Phase III clinical trial for the treatment of pulmonary arterial hypertension (PAH). Inhaled seralutinib, which is designed to act on both isoforms of the PDGFR, α and β, as well as the CSF1R and c-KIT pathways.
About the author
Emily J. Thompson
Emily J. Thompson, a Chartered Financial Analyst (CFA) with 12 years in investment research, graduated with honors from the Wharton School. Specializing in industrial and technology stocks, she provides in-depth analysis for Intellectia’s earnings and market brief reports.
Gossamer Bio Under Investigation as Stock Plummets 80.14%
- Investigation Launched: Pomerantz LLP is investigating Gossamer Bio, Inc. for potential securities fraud or unlawful business practices, highlighting serious concerns among investors regarding corporate governance.
- Trial Failure: On February 23, 2026, Gossamer announced that its Phase 3 PROSERA trial for pulmonary arterial hypertension failed to meet its primary endpoint, leading to a significant drop in market confidence.
- Stock Plunge: Following the trial failure announcement, Gossamer's stock price fell by $1.71, a staggering 80.14% decline, closing at $0.423 per share, reflecting investors' pessimism about the company's future prospects.
- Legal Implications: The investigation may result in Gossamer facing class action lawsuits, with Pomerantz LLP, a prominent securities litigation firm, potentially seeking compensation for affected investors, further exacerbating the legal risks the company faces.
See More
Gossamer Bio Q4 Earnings Beat Expectations with Strong Revenue Growth
- Earnings Report: Gossamer Bio's Q4 GAAP EPS of -$0.21 missed expectations by $0.02, indicating ongoing challenges in achieving profitability despite revenue growth.
- Revenue Surge: The company reported Q4 revenue of $13.8 million, a 47.8% year-over-year increase, exceeding market expectations by $6.28 million, reflecting strong product demand and overall performance improvement.
- Clinical Research Progress: Gossamer Bio discussed positive topline results from its PROSERA Phase 3 study in pulmonary arterial hypertension, potentially laying the groundwork for future market introduction and boosting investor confidence in its R&D pipeline.
- Market Reaction: Although the EPS fell short of expectations, the robust revenue growth and positive clinical study results may enhance the market's overall perception of Gossamer Bio, potentially driving a rebound in stock price.
See More
Gossamer Bio Reports 2025 Financial Results and Strategic Update
- PROSERA Study Results: Gossamer Bio's PROSERA Phase 3 study revealed that seralutinib improved six-minute walk distance (6MWD) by approximately +13.3 meters at 24 weeks, failing to meet the pre-specified statistical threshold, although a +20.0 meters improvement was observed in the high-risk subgroup, indicating potential efficacy in severe patients.
- SERANATA Study Enrollment Paused: The company has paused enrollment in the SERANATA study for PH-ILD to evaluate the implications of PROSERA results and engage with the FDA on potential regulatory pathways, reflecting a cautious approach to clinical trial design.
- Workforce Reduction and Cost Control: To better align resources with near-term priorities, the company implemented a reduction in force and other cost-containment measures aimed at optimizing capital allocation and focusing on regulatory and strategic planning for seralutinib.
- Financial Overview: As of December 31, 2025, the company reported cash and cash equivalents of $137 million, expected to fund operations and capital expenditures into Q1 2027, despite a net loss of $170.4 million, highlighting financial pressure alongside ongoing R&D investments.
See More
Investment Opportunities in Oversold Healthcare Stocks
- Gossamer Bio Performance Review: On February 23, Gossamer Bio announced topline results from the PROSERA Phase 3 study, indicating the drug's activity in pulmonary arterial hypertension patients despite narrowly missing the statistical threshold, resulting in a 76% stock drop over the past month, with an RSI of 26.3 indicating oversold conditions.
- Brainsway Clinical Data: On March 4, Brainsway disclosed new clinical data showing a significantly faster, non-invasive treatment for depression, with a 52-week low of $3.92 and an RSI of 19.1, suggesting its stock is also oversold.
- Definitive Healthcare Earnings: Definitive Healthcare posted inline Q4 earnings on February 26, with CEO Kevin Coop highlighting progress across strategic pillars, despite a 38% stock drop in the past month and an RSI of 28.1, indicating potential for a rebound.
- Market Trend Analysis: Benzinga Pro signals indicate potential breakout opportunities for both Gossamer Bio and Definitive Healthcare, with respective stock gains of 23.4% and 5.2% on Wednesday, providing investors with signals to explore opportunities in oversold healthcare stocks.
See More
Investment Opportunities in Oversold Healthcare Stocks
- Oversold Stocks Overview: In the healthcare sector, Gossamer Bio Inc, Brainsway Ltd, and Definitive Healthcare Corp have relative strength indices (RSI) near or below 30, indicating these stocks are significantly undervalued and may present buying opportunities for investors.
- RSI Indicator Interpretation: The relative strength index (RSI) serves as a momentum indicator that compares a stock's strength on up days versus down days, helping traders better assess short-term stock performance, particularly in oversold conditions.
- Market Opportunity Analysis: According to Benzinga Pro, assets are typically considered oversold when the RSI is below 30, providing investors with opportunities to identify potential rebound stocks within the healthcare sector that could yield substantial returns.
- Investment Strategy Recommendations: Investors should focus on the fundamentals and market dynamics of these oversold stocks to make informed investment decisions at the right time, thereby capitalizing on profit opportunities arising from market fluctuations.
See More
Gossamer Bio's Phase 3 Trial Misses Key Endpoint
- Trial Failure: Gossamer Bio's Phase 3 PROSERA trial missed its primary endpoint, resulting in a more than 60% drop in stock value, indicating extreme market pessimism regarding the company's future prospects.
- Guidance Misstep: CEO Faheem Hasnain's May 2025 statement anticipated results in February 2026 but failed to disclose that the trial's statistical significance threshold was set at 0.025, significantly higher than the conventional 0.05, leading to a mismatch between investor expectations and actual risk.
- Investor Confidence Eroded: The lack of transparency regarding the statistical hurdle left investors relying on management's forward-looking statements unable to assess the risk of a technical miss, potentially resulting in substantial financial losses.
- Potential Legal Action: Affected investors are encouraged to contact legal counsel to discuss their rights, highlighting increasing market scrutiny on corporate governance and disclosure practices.
See More
Gossamer Bio Under Investigation as Stock Plummets 80.14%
- Investigation Launched: Pomerantz LLP is investigating Gossamer Bio, Inc. for potential securities fraud or unlawful business practices, highlighting serious concerns among investors regarding corporate governance.
- Trial Failure: On February 23, 2026, Gossamer announced that its Phase 3 PROSERA trial for pulmonary arterial hypertension failed to meet its primary endpoint, leading to a significant drop in market confidence.
- Stock Plunge: Following the trial failure announcement, Gossamer's stock price fell by $1.71, a staggering 80.14% decline, closing at $0.423 per share, reflecting investors' pessimism about the company's future prospects.
- Legal Implications: The investigation may result in Gossamer facing class action lawsuits, with Pomerantz LLP, a prominent securities litigation firm, potentially seeking compensation for affected investors, further exacerbating the legal risks the company faces.
See More
Gossamer Bio Q4 Earnings Beat Expectations with Strong Revenue Growth
- Earnings Report: Gossamer Bio's Q4 GAAP EPS of -$0.21 missed expectations by $0.02, indicating ongoing challenges in achieving profitability despite revenue growth.
- Revenue Surge: The company reported Q4 revenue of $13.8 million, a 47.8% year-over-year increase, exceeding market expectations by $6.28 million, reflecting strong product demand and overall performance improvement.
- Clinical Research Progress: Gossamer Bio discussed positive topline results from its PROSERA Phase 3 study in pulmonary arterial hypertension, potentially laying the groundwork for future market introduction and boosting investor confidence in its R&D pipeline.
- Market Reaction: Although the EPS fell short of expectations, the robust revenue growth and positive clinical study results may enhance the market's overall perception of Gossamer Bio, potentially driving a rebound in stock price.
See More
Gossamer Bio Reports 2025 Financial Results and Strategic Update
- PROSERA Study Results: Gossamer Bio's PROSERA Phase 3 study revealed that seralutinib improved six-minute walk distance (6MWD) by approximately +13.3 meters at 24 weeks, failing to meet the pre-specified statistical threshold, although a +20.0 meters improvement was observed in the high-risk subgroup, indicating potential efficacy in severe patients.
- SERANATA Study Enrollment Paused: The company has paused enrollment in the SERANATA study for PH-ILD to evaluate the implications of PROSERA results and engage with the FDA on potential regulatory pathways, reflecting a cautious approach to clinical trial design.
- Workforce Reduction and Cost Control: To better align resources with near-term priorities, the company implemented a reduction in force and other cost-containment measures aimed at optimizing capital allocation and focusing on regulatory and strategic planning for seralutinib.
- Financial Overview: As of December 31, 2025, the company reported cash and cash equivalents of $137 million, expected to fund operations and capital expenditures into Q1 2027, despite a net loss of $170.4 million, highlighting financial pressure alongside ongoing R&D investments.
See More
Investment Opportunities in Oversold Healthcare Stocks
- Gossamer Bio Performance Review: On February 23, Gossamer Bio announced topline results from the PROSERA Phase 3 study, indicating the drug's activity in pulmonary arterial hypertension patients despite narrowly missing the statistical threshold, resulting in a 76% stock drop over the past month, with an RSI of 26.3 indicating oversold conditions.
- Brainsway Clinical Data: On March 4, Brainsway disclosed new clinical data showing a significantly faster, non-invasive treatment for depression, with a 52-week low of $3.92 and an RSI of 19.1, suggesting its stock is also oversold.
- Definitive Healthcare Earnings: Definitive Healthcare posted inline Q4 earnings on February 26, with CEO Kevin Coop highlighting progress across strategic pillars, despite a 38% stock drop in the past month and an RSI of 28.1, indicating potential for a rebound.
- Market Trend Analysis: Benzinga Pro signals indicate potential breakout opportunities for both Gossamer Bio and Definitive Healthcare, with respective stock gains of 23.4% and 5.2% on Wednesday, providing investors with signals to explore opportunities in oversold healthcare stocks.
See More
Investment Opportunities in Oversold Healthcare Stocks
- Oversold Stocks Overview: In the healthcare sector, Gossamer Bio Inc, Brainsway Ltd, and Definitive Healthcare Corp have relative strength indices (RSI) near or below 30, indicating these stocks are significantly undervalued and may present buying opportunities for investors.
- RSI Indicator Interpretation: The relative strength index (RSI) serves as a momentum indicator that compares a stock's strength on up days versus down days, helping traders better assess short-term stock performance, particularly in oversold conditions.
- Market Opportunity Analysis: According to Benzinga Pro, assets are typically considered oversold when the RSI is below 30, providing investors with opportunities to identify potential rebound stocks within the healthcare sector that could yield substantial returns.
- Investment Strategy Recommendations: Investors should focus on the fundamentals and market dynamics of these oversold stocks to make informed investment decisions at the right time, thereby capitalizing on profit opportunities arising from market fluctuations.
See More
Gossamer Bio's Phase 3 Trial Misses Key Endpoint
- Trial Failure: Gossamer Bio's Phase 3 PROSERA trial missed its primary endpoint, resulting in a more than 60% drop in stock value, indicating extreme market pessimism regarding the company's future prospects.
- Guidance Misstep: CEO Faheem Hasnain's May 2025 statement anticipated results in February 2026 but failed to disclose that the trial's statistical significance threshold was set at 0.025, significantly higher than the conventional 0.05, leading to a mismatch between investor expectations and actual risk.
- Investor Confidence Eroded: The lack of transparency regarding the statistical hurdle left investors relying on management's forward-looking statements unable to assess the risk of a technical miss, potentially resulting in substantial financial losses.
- Potential Legal Action: Affected investors are encouraged to contact legal counsel to discuss their rights, highlighting increasing market scrutiny on corporate governance and disclosure practices.
See More
