Vertex Pharmaceuticals: Maintains CF Leadership Position; Quick Take on ‘719 Update

Research evidence excerpt

J P M O R G A N

North America Equity Research

10 August 2026

Vertex Pharmaceuticals

Maintains CF Leadership Position; Quick Take on ‘719

Update

We expect the market to see this morning’s news on SION-719 as removing an

overhang on VRTX. Admittedly, based on our calls, VRTX investors had become

less concerned about this as a threat to the CF franchise as the summer went on;

however, the sweat chloride result still came in below any investor expectation we

had heard heading in. Indeed, the challenge this asset ran into delivering a SwCl

benefit on top of Trikafta in phase IIa (something that Alyftek has already done in

phase III) underlines the foresight in VRTX mgmt’s commentary on last week’s

earnings call that it is getting harder and harder to deliver improvements above and

beyond those delivered by Trikafta/Alyftrek. Looking ahead, we will watch for

VRTX’s PoC data for VX-828 in CF patients later this year, although given the

increasingly high bar in CF coupled with the lack of an imminent competitive

threat following today’s ‘719 data, we see VRTX in a position to accumulate data

from potentially multiple next-gen regimens before advancing any to late-stage

development.

Digging into the details, Sionna’s phase IIa PreciSION CF proof-ofconcept trial testing SION-719 on top of Trikafta delivered a ~1mmol/L

mean pbo-adjusted sweat chloride (SwCl) benefit (p=0.7). This is not close

to the high bar we considered associated with Alyftrek. In line with prior views

(published here), we see this as an overhang removed for Vertex that reaffirms

its leadership in CF.

Next gen products in VRTX pipeline, next topline read of ‘828 later this

year. With 2Q results (see here) VRTX reiterated their confidence in the value

of Alyftrek and described the bar from here as getting a greater % of patients

to SwCl of 30 mmol/L or lower. VRTX remains on track with its PoC trial for

next-gen CF product VX-828 with topline data readout this year (cohort

recently finished dosing), although we think mgmt may wait for data across the

next-gen products (including VX-582 and VX-272 in phase I) before deciding

which, if any, to advance based on potential to beat Alyftrek.

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