KYNB

FG-3246 / FG-3180 Program (metastatic castration-resistant prostate cancer, mCRPC)

• FG-3246 is a potential first-in-class CD46-targeted antibody drug conjugate (ADC), paired with companion PET imaging agent FG-3180 for patient selection, targeting a high unmet need in mCRPC.
• CD46 is a compelling target: it is highly expressed in 50%-70% of mCRPC tumors with limited normal tissue expression, upregulated during tumor progression, and has more uniform expression with lower interpatient variability than PSMA.
• Early clinical data demonstrates encouraging activity: the Phase I monotherapy trial showed an 8.7 month median rPFS, 36% PSA50 response, and 20% ORR (7.5 month median duration of response) in heavily pre-treated, unselected patients. The UCSF Phase I-B/II investigator study of FG-3246 + enzalutamide showed 10.1 months median rPFS and 40% PSA50 response in patients who progressed on only one prior ARPI.
• G-CSF primary prophylaxis, introduced after the Phase I trial, reduced Grade 3+ neutropenia, and is now incorporated into the ongoing Phase II trial design to reduce dose interruptions.
• The ongoing Phase II monotherapy trial (enrolling 75 post-ARPI pre-chemotherapy mCRPC patients) is on track to deliver an interim analysis in Q4 2026; 23 top-tier U.S. sites are active, and ~30% of enrolled patients have prior Pluvicto (Lutetium-177) treatment, with a pre-specified subgroup analysis for this population built into the trial.
• The Phase II trial design incorporates three improvements over Phase I to target a commercial-competitive median rPFS of 10+ months: testing the highest three Phase I doses, mandatory G-CSF prophylaxis, and enrolling earlier-stage patients (one prior ARPI, versus a median of five prior lines in Phase I).

Roxadustat Program (anemia from lower-risk myelodysplastic syndromes, LR-MDS)

• Roxadustat is an oral therapy targeting a large unmet need: 50,000 U.S. LR-MDS patients with anemia have no approved oral options, and current therapies work in less than 50% of patients.
• Post-hoc analysis of the prior Phase III MATTERHORN trial showed 36% of high transfusion burden roxadustat patients achieved 8+ weeks of transfusion independence, versus 7% for placebo, with consistent efficacy across both RS+ and RS- patient subgroups.
• The RS- patient segment (over 50% of all LR-MDS patients) represents a key differentiated opportunity, as leading therapy luspatercept has not demonstrated differentiated efficacy in RS- patients and is not indicated for second-line RS- use.
• The Phase III registrational trial protocol is finalized following FDA interactions, with a primary endpoint of 8-week transfusion independence at 24 weeks, and planned enrollment of sufficient RS+ and RS- patients to confirm efficacy across both subgroups. The trial is on track to initiate in Q4 2026.

• Kyntra Bio confirms current cash holdings provide a cash runway into 2028, enabling continued investment in its U.S. clinical pipeline.
• The interim analysis for the FG-3246 Phase II monotherapy trial remains on track to be delivered in Q4 2026, with mature rPFS data expected throughout 2027 as the trial progresses.
• Initiation of the roxadustat Phase III registrational trial in LR-MDS remains on track for Q4 2026, with management currently evaluating parallel paths for internal development (with additional capital raising) or strategic partnership, with a final decision to be made in the best interest of shareholders.
• No changes were made to prior financial or clinical milestone guidance; all stated timelines remain unchanged from previous disclosures.

Kyntra Bio is a clinical-stage biotech firm with two core development programs; no product segments have generated commercial revenue as of Q2 2026. Q2 2026 total revenue was -$1.5 million, compared to $1.3 million in Q2 2025. Total operating expenses were $16.1 million in Q2 2026, up from $13.4 million in the year-ago period. Research and development (R&D) expenses were $6.8 million in Q2 2026, compared to $5.9 million in Q2 2025. Selling, general and administrative (SG&A) expenses were $9.3 million in Q2 2026, up from $7.1 million in Q2 2025. Net income from continuing operations was $12 million ($2.96 per basic/diluted share) in Q2 2026, compared to a net loss of $13.7 million ($3.38 loss per share) in Q2 2025. As of June 30, 2026, Kyntra Bio held $95.7 million in combined cash equivalents, investments, and accounts receivable.

• All forward-looking statements (including clinical trial timelines, trial outcome expectations, regulatory and commercial opportunities) are subject to material risks that could cause actual results to differ materially from projections, with detailed risk factors available in Kyntra Bio's SEC filings (most recent Form 10-K and Form 10-Q).
• Clinical trial success is not guaranteed: futility assessment will be conducted at the FG-3246 Phase II interim analysis, and positive early data does not guarantee positive results in larger, later-stage trials.
• Tissue collection for exploratory research (including paired pre- and post-treatment biopsies) is limited by the nature of mCRPC (which is often localized to bone, with limited soft tissue available for biopsy) and patient burden, meaning some exploratory scientific questions may not be fully answered.
• The roxadustat Phase III initiation is contingent on either securing additional capital for internal development or reaching a strategic partnership agreement, introducing execution risk to the Q4 2026 initiation timeline.
• Changing standard of care dynamics in mCRPC (including increasing first-line use of PSMA-targeted Lutetium-177 therapies) could shift patient enrollment patterns and require adjustments to future Phase III trial design.

Q: What is the titration protocol for roxadustat in the upcoming Phase III trial, including timing and dose steps? / A: Dose adjustments (up or down) are made every six weeks based on combined benefit-risk assessment, including patient hemoglobin levels and the rate of hemoglobin rise. Dose adjustments occur in incremental intervals, not a direct jump from 2.5 mg/kg to 3.5 mg/kg, with formal titration guidance provided to all trial sites.

Q: Is initiation of the roxadustat Phase III trial contingent on securing a partner, and how did the positive MATTERHORN RS subgroup data change partnering and trial design considerations? / A: Management is running a parallel process, evaluating both internal development (requiring additional capital raising) and strategic partnership, with a final decision focused on shareholder value. The data showing efficacy across both RS+ and RS- patients highlights the large unmet need in RS- patients, which strengthens the program's commercial opportunity, and informed the Phase III design by mandating sufficient enrollment of both subgroups to confirm cross-population efficacy, with trial design centered on the key outcome variable of transfusion burden identified in the MATTERHORN analysis. Economic terms with AstraZeneca also factor into the decision: Kyntra owes a mid-single-digit royalty for independent development, and AstraZeneca receives 35% of Kyntra's economics if the program is partnered.

Q: What is the share of prior Lutetium-177 (Pluvicto)-treated patients in the FG-3246 Phase II trial, and is the company considering accelerated approval for this patient subgroup? / A: Approximately 30% of currently enrolled patients have prior Pluvicto treatment, and a pre-specified subgroup analysis for prior Pluvicto exposure is built into the trial statistical analysis plan. The share may increase over time as Pluvicto adoption grows for first-line mCRPC, and management is monitoring this trend to inform future Phase III design. While accelerated approval for this subgroup has not been formally planned, management will keep this option open and make a data-driven decision after Phase II interim results are available.

Q: How does Kyntra plan to position FG-3246 as a non-PSMA targeted therapy for mCRPC, and what is the long-term plan for roxadustat in first-line LR-MDS? / A: FG-3246 is being evaluated across all mCRPC patient subgroups, with the Phase II trial designed to generate data to inform the optimal commercial positioning. Early KOL feedback suggests FG-3246's CD46 targeting fills a key unmet need as a follow-up treatment after progression on PSMA-targeted therapies, as clinicians prefer to switch targets after PSMA therapy failure. For roxadustat, following the current registrational trial in refractory/prior ESA patients, the company's long-term lifecycle plan includes evaluating expansion into earlier lines of therapy for LR-MDS.