# Explore Slow-Release Formulation of a Peptide Therapeutic for Migraine

> **NIH NIH R43** · ACHERX · 2021 · $500,000

## Abstract

Abstract/Summary: We propose the investigation of slow-release formulations of a Calcitonin Gene-
Related Peptide (CGRP) antagonist for the treatment of migraine. We identified a series of
peptides, designed on the salmon calcitonin backbone, which due to a slow receptor off-rate
have an extended duration of action in vivo. In a rodent model measuring CGRP-induced
vasodilation, at the middle meningeal artery, our lead peptide antagonist ACX101 was far
superior, at a low dose of 20 mcg/kg, to a small molecule inhibitor dosed at 300 mcg/kg. While
a challenging assay to accomplish, it is a more relevant CGRP-related readout than the typical
assay where vasodilation was caused by capsaicin to study the effect of a CGRP antagonist or
antibody. Due to a complicated physiology, it is important to note that there is no generally
accepted assay for migraine that is clinically predictive. Small molecule antagonists from
Boehringer Ingelheim and Merck were dropped from the clinic due to compound-related
toxicity. Small molecule inhibitors are thus dose-limited, resulting in marginal benefits over
placebo control. Since ACX101 is composed of natural amino acids it will be cleared by the
kidneys, as small peptide fragments, thus circumventing the liver. ACX101 has also
demonstrated superior potency to a CGRP antibody in the same rodent assay where the
antibody was about 50% effective. Incidentally, clinical data from CGRP antibodies have
demonstrated reductions in migraine-related pain symptoms averaging 50%. ACX101 is fully
effective within 30 minutes and neutralizes CGRP-related vasodilation sustainably for over 90
minutes (the assay duration). Since peptide therapeutics are rapidly metabolized and cleared
physiologically, we propose slow-release formulations that extend drug efficacy from a few
days to two weeks. This would primarily address the needs of patients who suffer from low to
medium frequency migraine episodes (less than 15 days/month). The proposed formulation
choices have been clinically validated, resulting in a number of slow-release drugs with
efficacy extended to four months from a single dose form. The resulting therapeutic will
substantially benefit unserved patients if the preclinical efficacy and formulation choices
translate in the clinic. Benefitting from widely used manufacturing processes, both for peptide
synthesis and formulations, the cost of a peptide-based therapeutic will be substantially lower
than antibodies which are currently priced at close to $7000/year. Additionally, the proposed
formulations could be dosed as needed thus avoiding antibody therapeutics with substantially
longer half-lives that result in physiological effects of greater than 3 months.

## Key facts

- **NIH application ID:** 10141025
- **Project number:** 1R43NS120440-01
- **Recipient organization:** ACHERX
- **Principal Investigator:** Christopher Joseph Soares
- **Activity code:** R43 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2021
- **Award amount:** $500,000
- **Award type:** 1
- **Project period:** 2021-09-01 → 2022-12-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10141025

## Citation

> US National Institutes of Health, RePORTER application 10141025, Explore Slow-Release Formulation of a Peptide Therapeutic for Migraine (1R43NS120440-01). Retrieved via AI Analytics 2026-05-27 from https://api.ai-analytics.org/grant/nih/10141025. Licensed CC0.

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