Efaproxiral Sodium

**Semantic type:** Pharmacologic Substance

**Definition:** The sodium salt form of efaproxiral, a propanoic acid and allosteric modifier of hemoglobin, with radiosensitizing activity. Efaproxiral binds non-covalently to the hemoglobin tetramer, thereby decreasing hemoglobin-oxygen binding affinity. This results in an increase in oxygen levels in hypoxic tumor tissues; increasing tumor oxygenation reduces tumor radioresistance.

**Synonyms:** - EFAPROXIRAL SODIUM - Efaproxyn