Kyntra Bio Announces Positive Data from the Investigator-Sponsored Phase 1b/2 Study of FG-3246 in Combination with Enzalutamide in Patients with Metastatic Castration Resistant Prostate Cancer to Be Presented at ASCO GU 2026
Rhea-AI Summary
Kyntra Bio (NASDAQ: KYNB) reported positive investigator‑sponsored Phase 1b/2 data for FG-3246 plus enzalutamide in mCRPC. In 44 biomarker‑unselected patients the combination produced a composite response rate 21% overall and 40% in patients with only one prior ARPI; median rPFS was 7.0 months overall and 10.1 months for one‑prior ARPI patients. The MTD/recommended dose was 2.1 mg/kg FG-3246 with 160 mg/day enzalutamide. Higher FG-3180 PET uptake trended with PSA50 response (p=0.053). Phase 2 monotherapy interim analysis expected in 2H 2026.
Positive
- Composite response rate 21% overall
- Composite response rate 40% in patients with one prior ARPI
- Median rPFS 10.1 months in one‑prior ARPI subgroup
- MTD / recommended dose set at 2.1 mg/kg FG-3246 plus 160 mg/day enzalutamide
- FG-3180 PET uptake trended with higher PSA50 response (p=0.053)
Negative
- Median rPFS 7.0 months in the overall cohort
- Cumulative toxicities including peripheral neuropathy caused some treatment discontinuations
- Over 60% of patients had progressed on two or more prior ARPIs, limiting generalizability to earlier lines
Market Reaction – KYNB
Following this news, KYNB has declined 7.45%, reflecting a notable negative market reaction. Our momentum scanner has triggered 3 alerts so far, indicating moderate trading interest and price volatility. The stock is currently trading at $7.45. This price movement has removed approximately $3M from the company's valuation.
Data tracked by StockTitan Argus (15 min delayed). Upgrade to Silver for real-time data.
Key Figures
Market Reality Check
Peers on Argus
No peer stocks from the same sector were flagged in the momentum scanner, indicating the 6.12% move in KYNB appears company-specific to this FG-3246/FG-3180 clinical update rather than a sector-wide rotation.
Historical Context
| Date | Event | Sentiment | Move | Catalyst |
|---|---|---|---|---|
| Feb 17 | Conference participation | Neutral | -1.6% | Management announcing participation in upcoming healthcare investor conferences. |
Limited history is available; one recent conference-related announcement saw a mild negative reaction, offering little evidence of a consistent news-trading pattern.
In the past week, Kyntra Bio issued a conference participation update on Feb 17, 2026, outlining appearances at major healthcare investor events. That announcement, tagged as conferences, saw a modest -1.61% move in the stock. Today’s ASCO GU 2026 clinical data release on FG-3246 and FG-3180 represents a more substantive pipeline milestone, contrasting with the prior investor-relations focused news and offering new detail on efficacy, safety, and biomarker strategy in mCRPC.
Market Pulse Summary
The stock is down -7.5% following this news. A negative reaction despite positive clinical signals would have contrasted with the reported median rPFS of 7.0 months overall and 10.1 months in patients with one prior ARPI. Past news flow shows only a modest -1.61% move on a conference announcement, giving limited evidence of a strong sell-on-news pattern. Any sharp downside could reflect position-driven trading rather than a clear shift in the FG-3246 development story.
Key Terms
radiographic progression free survival medical
pet imaging medical
maximum tolerated dose medical
recist v1.1 medical
overall survival medical
AI-generated analysis. Not financial advice.
- FG-3246 and enzalutamide combination therapy, in biomarker unselected patients with androgen receptor pathway inhibitor (ARPI)-treated, taxane-naïve metastatic castration-resistant prostate cancer (mCRPC), led to a median radiographic progression free survival (rPFS) of 7.0 months in the overall study cohort, with median rPFS of 10.1 months observed in patients who progressed on only one prior ARPI
- Higher tumor uptake of FG-3180, a CD46 directed PET imaging agent, demonstrated a trend towards higher probability of PSA50 response, highlighting its potential for patient selection
- Combination therapy had a similar safety and exposure profile to the previous FG-3246 Phase 1 monotherapy trial
- Results further validate key FG-3246 Phase 2 monotherapy design elements, most importantly the inclusion of patients who have progressed on only one prior ARPI and integration of baseline FG-3180 PET for all enrolled patients
- FG-3246 Phase 2 monotherapy trial on track for interim analysis in 2H 2026
SAN FRANCISCO, Feb. 23, 2026 (GLOBE NEWSWIRE) -- Kyntra Bio (Nasdaq: KYNB), formerly FibroGen (Nasdaq: FGEN), today announced that the data on anti-tumor activity of FG-3246 in combination with enzalutamide in patients with metastatic castration-resistant prostate cancer (mCRPC) from the investigator-sponsored Phase 1b/2 study will be presented at the 2026 American Society of Clinical Oncology Genitourinary Cancers Symposium (ASCO GU), taking place February 26-28, 2026 in San Francisco, CA.
“The results from this Phase 1b/2 investigator-initiated study demonstrate encouraging preliminary anti-tumor activity of FG-3246 in combination with enzalutamide in patients with mCRPC. Notably, the 10.1 months of rPFS in patients with only one prior ARPI underscores the potential of FG-3246 in earlier lines of therapy,” commented Dr. Rahul Aggarwal, Professor of Medicine at the University of California San Francisco, and Principal Investigator of the study. “The positive trend observed in the association between tumor uptake of FG-3180 (CD46-targeting PET) and PSA50 response, though from a small number of patients, is especially intriguing and I’m excited to see the potential utility of this biomarker further explored in the Phase 2 monotherapy study.”
“These data from the investigator sponsored trial expand on the clinically meaningful results previously observed with FG-3246,” said Thane Wettig, Chief Executive Officer of Kyntra Bio. “The 10.1 months of median rPFS observed in patients progressing on only one prior ARPI, and the mitigation of neutropenia related adverse events with prophylactic G-CSF are especially encouraging as they further validate our Phase 2 monotherapy trial design. We look forward to sharing the interim analysis of the Phase 2 monotherapy trial in the second half of 2026 as well as further characterizing the potential utility of FG-3180 as a patient selection biomarker.”
The presentation includes data from 44 biomarker unselected patients with progressive metastatic castration-resistant prostate cancer, 17 of which were enrolled in the Phase 1b dose escalation portion of the study. Eligibility criteria for the trial included patients who progressed on at least one prior ARPI while patients who were treated with prior chemotherapy in the castration-resistant setting were excluded. Over
FG-3246 combined with enzalutamide demonstrated anti-tumor activity with a composite response rate of
Combination therapy of FG-3246 and enzalutamide demonstrated a similar safety profile as was observed in the previous Phase 1 monotherapy trial of FG-3246. Neutropenia risk was successfully mitigated with use of G-CSF prophylaxis. The most frequent TRAEs with the combination therapy included fatigue, peripheral neuropathy, anorexia, and dysgeusia. Cumulative toxicities, including peripheral neuropathy, led to treatment discontinuation for some patients.
The poster presentation, titled “A phase 1b/2 study of FOR46 (FG-3246) in combination with enzalutamide (enza) in patients with metastatic castration resistant prostate cancer (mCRPC)”, is scheduled for the poster session taking place on February 26, 2026 from 11:30 AM to 12:45 PM PT.
FG-3246 is currently being evaluated in a Phase 2 monotherapy trial with interim data expected in the second half of 2026. The trial also includes treatment with FG-3180, a CD46-directed PET imaging agent, which will measure expression levels of CD46 positive lesions. This will enable further assessment of the correlation between CD46 expression and response to FG-3246 and the potential of FG-3180 to serve as a biomarker to aid in patient selection in future trials of FG-3246.
About FG-3246 and FG-3180
FG-3246 (FOR46) is a potential first-in-class fully human antibody-drug conjugate (ADC), exclusively in-licensed from Fortis Therapeutics, and is being developed by Kyntra Bio for metastatic castration-resistant prostate cancer and potentially other tumor types. FG-3246 binds to an epitope of CD46, a cell receptor target, that induces internalization upon antibody binding, is present at high levels in prostate cancer and other tumor types and demonstrates very limited expression in most normal tissues. FG-3246 is comprised of an anti-CD46 antibody, YS5, linked to the anti-mitotic agent, MMAE, which is a clinically and commercially validated ADC payload. FG-3246 has demonstrated anti-tumor activity in both preclinical and clinical studies. FG-3180 is a companion diagnostic PET imaging agent, using the same CD46-targeting antibody together with an 89Zr tracker. To date, FG-3180 demonstrated specific uptake in CD46 positive tumors and is currently being evaluated as a biomarker for its potential to inform patient selection.
About the Phase 1b/2 Study of FG-3246 in Combination with Enzalutamide
This Phase 1b/2 study is an investigator-sponsored trial being conducted at the University of California San Francisco to evaluate FG-3246 (FOR46) in combination with enzalutamide in patients with metastatic castration-resistant prostate cancer (mCRPC) after prior progression on at least one androgen receptor pathway inhibitor. The primary objective for the Phase 1b portion of the study is to determine the maximally tolerated dose (MTD) and recommended Phase 2 dose of FG-3246 in combination with enzalutamide in patients with mCRPC. The objectives of the Phase 2 portion of the study are to determine the composite response rate (CRR), proportion of participants with a greater than or equal to
About Kyntra Bio
Kyntra Bio is a biopharmaceutical company focused on development of novel therapies in oncology and rare disease. Roxadustat (爱瑞卓®, EVRENZO™) is currently approved in Europe, Japan, and numerous other countries for the treatment of anemia in chronic kidney disease (CKD) patients on dialysis and not on dialysis. The Company continues to evaluate the development plan for the Phase 3 trial of roxadustat in anemia associated with lower-risk myelodysplastic syndromes (LR-MDS) in the U.S. FG-3246 (also known as FOR46), a first-in-class antibody-drug conjugate (ADC) targeting CD46, is in Phase 2 development for the treatment of metastatic castration-resistant prostate cancer. This program also includes the development of FG-3180, an associated CD46-targeted PET biomarker. For more information, please visit www.kyntrabio.com.
Forward-Looking Statements
This release contains forward-looking statements regarding Kyntra Bio’s strategy, future plans and prospects, including statements regarding its commercial products and clinical programs and those of its partners Fortis and UCSF. These forward-looking statements include, but are not limited to, statements regarding the efficacy, safety, and potential clinical or commercial success of Kyntra Bio products and product candidates, statements regarding the potential effectiveness of FG-3180 as a biomarker or predictor of response rate, and any forward looking statements regarding the design, efficacy or safety results of our ongoing Phase 2 monotherapy trial of FG-3246. These forward-looking statements are typically identified by use of terms such as “may,” “will”, “should,” “on track,” “could,” “expect,” “plan,” “anticipate,” “believe,” “estimate,” “predict,” “potential,” “continue” and similar words, although some forward-looking statements are expressed differently. Kyntra Bio’s actual results may differ materially from those indicated in these forward-looking statements due to risks and uncertainties related to the continued progress and timing of its various programs, including the enrollment and results from ongoing and potential future clinical trials, and other matters that are described in Kyntra Bio’s most recent Annual Report on Form 10-K and Quarterly Report on Form 10-Q, each as filed with the Securities and Exchange Commission (SEC), including the risk factors set forth therein. Investors are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this release, and Kyntra Bio undertakes no obligation to update any forward-looking statement in this press release, except as required by law.
For Investor Inquiries:
David DeLucia, CFA
Senior Vice President and Chief Financial Officer
ir@kyntrabio.com
FAQ
What were the key efficacy results for FG-3246 plus enzalutamide in the ASCO GU 2026 poster for KYNB?
How might FG-3180 PET imaging affect patient selection for FG-3246 (KYNB) trials?
What dose of FG-3246 and enzalutamide was recommended from the Phase 1b/2 study presented by KYNB?
When should investors expect additional FG-3246 data from KYNB's Phase 2 monotherapy trial?
What safety issues were reported for the FG-3246 plus enzalutamide combination in KYNB's data?
How many patients were included in the investigator‑sponsored FG-3246 plus enzalutamide study presented by KYNB?
