Connexa (KNSA) Q3 2025: Arcalyst Prescriber Base Expands by 350, Underpinning Guidance Hike

October 28, 2025 | By EarningsIQ Research

Connexa’s Arcalyst franchise delivered its largest-ever quarterly prescriber gain, supporting a $40 million upward revision to full-year sales guidance. Strategic focus on earlier-line use and digital engagement is accelerating penetration, but management signals the addressable market remains largely untapped. Investors should watch execution on KPL387’s phase progression and ongoing margin discipline as catalysts for further value creation.

Summary

• Prescriber Expansion Accelerates: Arcalyst added over 350 new prescribers in Q3, its highest quarterly increase since launch.
• Earlier-Line Adoption Gains Traction: Physicians are increasingly utilizing Arcalyst after first recurrence, broadening the eligible patient pool.
• Pipeline and Market Opportunity Remain Large: Only 15% penetration into the multiple recurrence segment highlights significant runway for both Arcalyst and KPL387.

Performance Analysis

Connexa’s Q3 performance was defined by robust Arcalyst revenue growth, driven by both a surge in new prescribers and an increase in patient duration on therapy. Arcalyst revenue rose 61% year-over-year, reflecting increased adoption of IL-1 alpha and beta inhibition as standard of care for recurrent pericarditis. The company’s commercial execution delivered a record 350-plus new prescribers, bringing the cumulative total to over 3,825, with 28% writing for multiple patients. This broadening base is a direct result of targeted sales efforts, digital marketing enhancements, and growing clinical confidence post-ACC guideline updates.

Operating expenses rose 29% year-over-year, but were outpaced by topline gains, leading to a swing from net loss to net income. Collaboration profit more than doubled, up 118% year-over-year, as steady cost of goods and marketing spend leveraged higher sales. Cash flow remained positive, with a $44 million increase in the cash balance, further strengthening Connexa’s financial position.

• Longer Therapy Duration: Average patient duration on Arcalyst reached 32 months, supporting durable revenue streams and high patient satisfaction.
• Gross-to-Net Dynamics: Gross-to-net adjustments improved to 8.9%, down from 9.5% in Q2, in line with historical seasonal patterns.
• Commercial Leverage: Collaboration expenses tracked with revenue growth, but profit split and cost controls preserved margin expansion.

Management’s confidence in the trajectory was underscored by a $40 million guidance raise for full-year Arcalyst net sales, now expected between $670 million and $675 million.

Executive Commentary

Strategic Positioning

1. Arcalyst: Penetration and Standard of Care Momentum

Arcalyst, IL-1 alpha and beta inhibitor, is rapidly becoming the treatment of choice for recurrent pericarditis as clinical guidelines and real-world data converge. Only 15% of the multiple recurrence patient population has been penetrated, leaving substantial headroom. The label’s agnosticism to number of recurrences enables targeting of both early and late-stage patients, supporting continued expansion.

2. Commercial Execution: Digital and Data-Driven Outreach

Connexa’s commercial team is leveraging AI and digital marketing to identify high-potential prescribers and optimize sales force deployment. This approach has driven both breadth (more prescribers) and depth (repeat prescribers), especially as underdiagnosis and misdiagnosis remain prevalent. The company’s patient support program, Connexa One Connect, further facilitates access and adherence.

3. Pipeline Advancement: KPL387 as Next-Gen Growth Driver

KPL387, a fully owned monoclonal antibody targeting IL-1 receptor, is advancing through Phase 2/3 development with orphan drug designation now secured. Surveys indicate strong physician and patient preference for its monthly auto-injector profile, suggesting it may unlock additional market segments upon approval. The dose-focusing data expected in the second half of 2026 will be pivotal for future positioning.

4. Market Expansion: Early Recurrence and Unmet Need

Physicians are increasingly prescribing Arcalyst after first recurrence, now accounting for roughly 20% of new starts. This earlier-line use reflects growing comfort with the therapy and a strategic shift in the treatment paradigm, as reinforced by updated ACC guidelines and real-world registry data showing steroid-sparing benefits.

Key Considerations

Connexa’s Q3 results reinforce its position as the category leader in recurrent pericarditis, but the company’s long-term trajectory will depend on its ability to sustain commercial momentum and execute on pipeline milestones.

Key Considerations:

• Guideline-Driven Adoption: ACC’s endorsement of IL-1 inhibition as second-line therapy is catalyzing earlier and broader use among prescribers.
• Commercial Infrastructure: AI-enabled targeting and digital outreach are enhancing efficiency in a widely dispersed patient population.
• Patient Retention and Satisfaction: High average therapy duration and positive patient feedback underpin recurring revenue and brand loyalty.
• Pipeline Differentiation: KPL387’s monthly dosing and orphan drug status could further expand the IL-1 franchise, pending successful Phase 2/3 outcomes.

Risks

Competition from emerging therapies, especially inflammasome inhibitors, could pressure Arcalyst’s share if new data shows comparable efficacy. The company’s growth remains tied to continued expansion in a still underdiagnosed market, and any disruption in payer access or regulatory setbacks for KPL387 could slow momentum. Collaboration expenses, while leveraged, will rise with revenue and could compress margins if sales growth moderates.

Forward Outlook

For Q4 2025, Connexa expects:

• Continued sequential growth in Arcalyst revenue, with typical year-end industry dynamics.
• Operating expenses to track with commercial expansion and pipeline investment.

For full-year 2025, management raised net sales guidance to:

• $670 million to $675 million for Arcalyst (up from $625-$640 million prior)

Management emphasized sustained prescriber growth, earlier-line adoption, and pipeline data readouts as key drivers for future performance.

• Focus on expanding both breadth and depth of prescribing base
• Anticipation of KPL387 Phase 2/3 data in second half of 2026

Takeaways

Connexa’s commercial flywheel is accelerating, but the company’s future value hinges on unlocking further market penetration and successful pipeline execution.

• Prescriber Base Expansion: The largest-ever quarterly increase in new prescribers demonstrates growing confidence and market validation.
• Strategic Shift to Early-Line Use: Physician willingness to treat after first recurrence is broadening the addressable market and accelerating revenue growth.
• Pipeline Execution Remains Critical: KPL387’s progress and differentiation will be closely watched as a catalyst for future growth and competitive defense.

Conclusion

Connexa’s Q3 results underscore the power of strong commercial execution and a robust clinical narrative in driving franchise value. With prescriber momentum and a disciplined financial approach, the company is well positioned, but must continue to deliver on both commercial and pipeline fronts to sustain long-term leadership in recurrent pericarditis.

Industry Read-Through

Connexa’s performance signals an inflection in the adoption of targeted immunomodulation for rare inflammatory diseases, with updated clinical guidelines and digital commercialization accelerating uptake. The company’s success in expanding the prescriber base and leveraging AI for sales efficiency may serve as a model for other specialty pharma peers targeting fragmented, underdiagnosed populations. Competitors developing inflammasome or cytokine pathway inhibitors should note the growing physician comfort with biologics and the importance of payer access and patient support programs in driving durable adoption.

KNSA Healthcare Pharmaceuticals Rare Disease Immunology Commercialization Pipeline