Septerna: Phase 1 Data in Healthy Volunteers HP-And-Coming in 1Q27; Model Update

Research evidence excerpt

J P M O R G A N

North America Equity Research

18 August 2026

Septerna

Phase 1 Data in Healthy Volunteers HP-And-Coming in

1Q27; Model Update

Overweight

SEPN, SEPN US

Price (18 Aug 26):$43.80

▲Price Target (Dec-27):$48.00

Prior (Dec-26):$38.00

We are updating our model post 2Q26 results and establishing a Dec 2027 price target

of $48. Overall, while we acknowledge SEPN’s strong performance YTD (~+57% vs

NBI +~22%), we see several opportunities for further upside for SEPN from current

levels as the potency/versatility of the platform is validated over time across its novel

product candidates and see the phase 1 data for SEP-479 (an oral, small molecule

PTH1R agonist for hypoparathyroidism; HP) in healthy volunteers that is on the

horizon as representing a key milestone to potentially continue to validate the

platform. Reiterate Overweight.

Phase 1 trial for SEP-479 ongoing… Septerna expects to report phase 1 data

for SEP-479 from both the SAD and MAD cohorts (including serum calcium

and endogenous serum PTH) in healthy volunteers in 1Q27 (from prior late

2026 or early 2027). As context, Septerna indicated that based on

pharmacokinetic (PK) data from the ongoing phase 1 clinical trial, the

observed elimination half-life of SEP-479 is ~3-4 days (“at the longer end” of

its preclinical estimates), which it anticipates will support once-daily dosing;

to fully characterize steady-state PK, dosing for the MAD cohorts will be

extended to 14 days. We see this approach as interesting based on the target of

PTH1R, which has been validated by Ascendis Pharma’s Yorvipath1 .

On SEP-631 next steps… Further, for SEP-631 (an oral, small molecule

MRGPRX2 NAM), the company noted it is evaluating development strategies

for “capital-efficient” and “signal-finding” clinical studies in mast cell-driven

diseases with high unmet need to provide derisking before initiating larger

studies, a decision that was made on the heels of competitor data.

On other efforts... Finally, Septerna continues to progress toward

development candidate selection for its TSHR NAM program, with the goal of

delivering a potential disease-modifying oral treatment for Graves’ disease and

…