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Phthalin (PHENOLPHTHALEIN)

FDA-approved withdrawn Small molecule Quality 35/100

Phenolphthalein, marketed as Phthalin, is a drug primarily indicated for headache, operating through the inhibition of thymidylate synthase, an enzyme crucial for DNA synthesis. Its key competitive advantage lies in its unique mechanism of action, distinguishing it from same-class competitors such as oxyphenisatine, bisacodyl, castor oil, and sodium picosulfate. The primary risk to Phenolphthalein is the expiration of its key composition patent in 2028, which could lead to increased competition from generics.

At a glance

Generic namePHENOLPHTHALEIN
Drug classphenolphthalein
TargetThymidylate synthase, Thymidylate synthase
ModalitySmall molecule
Therapeutic areaOncology
PhaseFDA-approved

Approved indications

Common side effects

No common side effects on file.

Key clinical trials

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results

Competitive intelligence

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