INSP Shares Down Despite Strong Clinical Data From Inspire V Trials

Inspire Medical Systems INSP recently unveiled promising clinical data from its Inspire V system at the ISSS and AAO-HNS meetings, showcasing strong safety, enhanced respiratory sensing and improved patient adherence. The findings, based on results from Singapore and a limited U.S. market release, highlight the company’s continued innovation in treating obstructive sleep apnea through minimally invasive neurostimulation.

The positive outcomes reinforce INSP’s technological leadership and are expected to strengthen physician confidence, support broader adoption and position the Inspire V system for deeper penetration in both the United States and international markets.  

Likely Trend of INSP Stock Following the News

Following the announcement, the company's shares lost 6.2% on Friday’s closing. In the year-to-date period, shares have plunged 59.5% against the industry’s 27.2% growth. The S&P 500 has gained 12.2% in the same time frame.

However, the strong Inspire V study data is a clear win for INSP, setting the stage for faster adoption and stronger revenue growth. With improved safety, shorter surgical times and higher patient adherence, physicians are likely to favor the new system, driving higher implant volumes and repeat utilization. These outcomes not only validate INSP’s innovation pipeline but also enhance its competitive position in the growing sleep apnea market, supporting margin expansion and long-term shareholder value.

INSP currently has a market capitalization of $2.22 billion. It has an earnings yield of 1.48%, higher than the industry’s negative 1.26%. In the last reported quarter, INSP delivered an earnings surprise of 104.6%.

More on the Study Data

The Inspire V system was first evaluated through a clinical trial conducted in Singapore across two centers, enrolling 44 patients who were being followed for six months post-implant. All procedures were completed successfully, with surgeons reporting a 20% reduction in surgical times compared to the previous Inspire IV device.

The Inspire V system integrates respiratory sensing within the neurostimulator itself, removing the need for a separate pressure-sensing lead used in earlier models. The primary endpoint, inspiratory phase overlap percentage, showed superior results for Inspire V at 87.1% compared with 79.4% for Inspire IV, with a non-inferiority margin of 4.6%.

At a mean follow-up of 246 days, average patient adherence was 5.5±1.7 hours per night, and the median Apnea Hypopnea Index (AHI) improved from 34.4 events per hour at baseline to 8.3 events per hour at six months. The safety profile remained strong, with only two patients requiring short-term postoperative antibiotics for wound care.

In the United States, a limited market release of Inspire V was conducted at 10 leading centers involving 101 patients. All device implantations were successfully completed with no serious adverse events. At the 60-day follow-up, all patients were actively using the therapy, with an average stimulation amplitude of 1.7 volts and average nightly usage of 6.8 hours.

Subsequent sleep study data from the first 34 patients demonstrated a median reduction in AHI from 30 to 4.5 events per hour, while therapy adherence and stimulation amplitude remained stable. Single-site experiences further validated the system’s efficiency, with Massachusetts Eye and Ear Infirmary reporting an average surgical time of 34.5 minutes and Colorado ENT and Allergy noting increased implant volumes per surgery day with Inspire V compared to Inspire IV.

Favorable Industry Prospects for INSP

Per a report by Grand View Research, the global neurostimulation devices market size was estimated at USD 5.6 billion in 2022 and is projected to reach USD 14.8 billion by 2030 at a CAGR of 12.8% from 2023 to 2030.

Some of the key factors driving the market include the growing geriatric population, the introduction of technologically advanced products, escalating product demand as an add-on therapy, an increasing incidence of chronic diseases, such as migraine and epilepsy, and the presence of highly unmet medical needs in these disease segments.

INSP’s Zacks Rank & Key Picks

Currently, INSP carries a Zacks Rank #5 (Strong Sell).

Some better-ranked stocks in the broader medical space are Masimo MASI, Merit Medical System MMSI and West Pharmaceutical Services WST. Each stock presently carries a Zacks Rank #2 (Buy). You can see the complete list of today’s Zacks #1 Rank (Strong Buy) stocks here.

Masimo shares have lost 10.4% so far this year compared with the industry’s 7.4% decline. Estimates for the company’s 2025 earnings per share have increased 1.3% to $5.30 in the past 30 days.

MASI’s earnings beat estimates in each of the trailing four quarters, the average surprise being 13.8%. In the last reported quarter, it posted an earnings surprise of 8.1%.

Estimates for Merit Medical’s 2025 earnings per share have increased 0.8% to $3.63 in the past 60 days. Shares of the company have lost 13.8% so far this year against the industry’s 1.1% growth.

MMSI’s earnings surpassed estimates in each of the trailing four quarters, the average surprise being 12.92%. In the last reported quarter, it delivered an earnings surprise of 17.44%.

Estimates for West Pharmaceutical’s 2025 earnings per share have increased 1.2% to $6.74 in the past 60 days. Shares of the company have lost 18.2% so far this year against the industry’s 1% growth.

WST’s earnings beat estimates in each of the trailing four quarters, the average surprise being 16.81%. In the last reported quarter, it delivered an earnings surprise of 21.85%.

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This article originally published on Zacks Investment Research (zacks.com).

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