Why Is Rare Endocrine Disorder-Focused Spruce Biosciences Stock Plummeting On Thursday?

Wednesday, Spruce Biosciences Inc SPRB released topline results from its CAHmelia-203 Phase 2b study of tildacerfont in adult classic congenital adrenal hyperplasia (CAH) and its CAHptain-205 study of tildacerfont in pediatric classic CAH.

CAH refers to a group of genetic disorders that involve the adrenal glands, a pair of small organs located above the kidneys.

The CAHmelia-203 study did not achieve the primary efficacy endpoint of the assessment of dose response for the change in A4 from baseline to week 12.

• 200mg QD of tildacerfont demonstrated a placebo-adjusted reduction from baseline in A4 of -2.6% at week 12 with a non-significant p-value.
•  Compliance with study medication and GC was low, with approximately 50% of patients reporting 80% or greater compliance, resulting in lower-than-expected tildacerfont exposure.
•  Tildacerfont was generally safe and well tolerated at all doses with no treatment-related serious adverse events (SAEs). Most adverse events were reported as mild to moderate.s

CAHptain-205 study enrolled 30 children.

• Tildacerfont was generally safe and well tolerated at all dose ranges with no treatment-related SAEs reported.
•  Preliminary pharmacokinetic analysis suggests that tildacerfont is cleared more rapidly in children than in adult CAH patients.
•  73% of all patients (22 of 30) met the efficacy endpoint of A4 or GC reduction from baseline at 12 weeks of treatment with tildacerfont.
•  70% of patients with elevated baseline A4 values (16 of 23 patients) demonstrated an A4 reduction at week 4.
•  The company says data from the CAHptain-205 study supports further dose-ranging across additional cohorts.

The company is also conducting CAHmelia-204 Phase 2b study assessing glucocorticoid (GC) reduction, a potentially registrational endpoint in adult CAH patients on supraphysiologic GC doses with normal or near normal levels of A4. Topline results are expected in Q3 2024.

In January, Spruce Biosciences said it completed enrollment in its CAHmelia-204 trial, with 100 patients exceeding the target enrollment of 90.

The company says resource prioritization and cost reductions, including termination of the CAHmelia-203 trial and a reduction in force of approximately 21%, will extend the cash runway through the end of 2025, including beyond anticipated topline results from CAHmelia-204 and additional dose-ranging data from CAHptain-205.

Price Action: SPRB shares are down 77.80% at $1.15 during the premarket session on the last check Thursday.