Boston Scientific: Watchman in two parts - what it means for the total

Research evidence excerpt

Boston Scientific: Watchman in two parts - what it means for the total

Summary table for scenarios

Our base case assumes 20% of standalone Watchman

cases done go away in 2027 using 2025 as a baseline.

Our base case assumes 20% of standalone Watchman cases done go away in 2027 using

2025 as a baseline. This means 8% US Watchman growth in 2027. A downside case has

25% of standalone Watchman going away by 2027 and continue to decline in 2028,

assuming little help from FDA label and NCD from potential delays or denial and

increased caution around Watchman’s stroke risk. There could also be share loss from

Amulet 2.0 in 2028. An upside case assumes FDA label expansion starts to help volumes

in 2027 with further acceleration in 2028 from an NCD update opening up the patient

pool.

FDA label and NCD could help Watchman reverse course

We think standalone Watchman referrals are likely slowing given numerically higher

stroke in CHAMPION vs high expectations and Stat sig higher stroke in the Watchman

cohort with no prior ablation. Referral sources are likely re-evaluating Watchman for

softer indication candidates. However, an FDA label expansion could help Watchman

reverse course before the NCD (soft but indicated candidates can pick back up). A

positive update to the NCD can further expand the pool to currently non-indicated

patients. In our upside case, we model standalone Watchman reversing declines in 2027

and moving to double digits growth in 2028.

Exhibit 1: Our base case assumes 20% of standalone Watchman cases go away vs 2025 baseline,

downside case assumes 25% of cases go away

2026 2027 2028

Base case - Standalone Watchman growth (12.4%) (7.2%) 0.0%

Base case - Total US Watchman growth 4.5% 8.2% 12.7%

Downside case - Standalone Watchman growth (12.6%) (12.9%) (9.0%)