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Semi-Synthetic Penicillin

Cubist Pharmaceuticals LLC, a subsidiary of Merck & Co., Inc. (Rahway, New Jersey USA) · FDA-approved active Small molecule

Semi-synthetic penicillins inhibit bacterial cell wall synthesis by binding to penicillin-binding proteins and blocking peptidoglycan cross-linking.

Semi-synthetic penicillins inhibit bacterial cell wall synthesis by binding to penicillin-binding proteins and blocking peptidoglycan cross-linking. Used for Bacterial infections susceptible to semi-synthetic penicillins (specific agents vary: e.g., ampicillin for gram-positive and some gram-negative infections; amoxicillin for respiratory and urinary tract infections).

At a glance

Generic nameSemi-Synthetic Penicillin
Also known asSSP, nafcillin, oxacillin, cloxacillin
SponsorCubist Pharmaceuticals LLC, a subsidiary of Merck & Co., Inc. (Rahway, New Jersey USA)
Drug classBeta-lactam antibiotic (semi-synthetic penicillin)
TargetPenicillin-binding proteins (PBPs); bacterial cell wall peptidoglycan
ModalitySmall molecule
Therapeutic areaInfectious Disease
PhaseFDA-approved

Mechanism of action

Semi-synthetic penicillins are beta-lactam antibiotics derived from the natural penicillin nucleus with chemical modifications to improve stability, spectrum, or pharmacokinetics. They work by irreversibly inhibiting transpeptidase enzymes that cross-link peptidoglycan strands in the bacterial cell wall, leading to cell wall weakening and bacterial lysis. These modifications allow them to resist certain beta-lactamases and extend activity against gram-negative organisms compared to natural penicillins.

Approved indications

Common side effects

Key clinical trials

Primary sources

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

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