Company: LBRX
Filing Date: 2025-08-22
Form Type: S-1
Source: 0001193125-25-186467
Chunk: 199

Company: LB PHARMACEUTICALS INC
Filing Date: 2025-08-22
Form: S-1
Chunk 199
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 mg and 75 mg cohorts, respectively. The exploratory 100 mg cohort showed a
16.1-point decrease in PANSS total score at Week 4. The placebo cohort had a 9.3-point decrease in PANSS total score. We included a number of measures in this Phase 2
trial in order to reduce the risk of an elevated placebo rate including consistent, frequent, and close engagement with clinical sites, the use of a third-party vendor to help identify and exclude professional patients from the trial, and a
centralized review of PANSS ratings to ensure consistency and quality control throughout the trial. When adjusted for placebo-response, the 50 mg cohort achieved a five-point decrease (p=0.0009) and the 75 mg cohort achieved a 4.7-point decrease (p=0.0022) in PANSS total score. Despite the highest dose cohort being exploratory and not sized to detect a statistically significant difference, the 100 mg cohort demonstrated a 6.8-point decrease (nominal p=0.0017) in PANSS total score when adjusted for placebo, which did achieve statistical significance.

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Least square (LS) mean change from baseline in PANSS total score.

The decrease in PANSS total score was observed as early as the first measurement on Day 8 with improvement seen through Week 4 across all
three dose cohorts.

Change in PANSS total score from baseline over time.

At Week 4, the 50 mg, 75 mg, and 100 mg groups showed effect sizes of 0.61, 0.41, and 0.83, respectively, as highlighted in the table below.
Effect size is calculated by taking the difference in average observed PANSS change among completers between two groups (an active treatment arm and placebo) and dividing it by a single measure of variability that combines both groups’
spreads—also called the observed pooled standard deviation. The observed pooled standard deviation averages how much individual patients’ score changes scatter around their group’s mean. Clinicians value effect size because it
conveys not just how large the average PANSS improvement is, but also how consistently patients respond. Even if two treatments reduce PANSS by the same amount on average, the one with less scatter (i.e., a lower observed pooled standard deviation)
will have a higher effect size—and gives a clinician more confidence that a higher proportion of patients will see that same benefit.

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| Dose of LB-102 |     |