Ozanimod is a selective sphingosine-1-phosphate (S1P) receptor modulator used as an immunomodulatory active pharmaceutical ingredient. It is a small-molecule pharmaceutical compound developed for the treatment of relapsing forms of multiple sclerosis and moderately to severely active ulcerative colitis in adults. Ozanimod is marketed as an oral medicine and is formulated commercially as ozanimod hydrochloride.
The free-base ozanimod has the molecular formula C₂₃H₂₄N₄O₃ and molecular weight 404.5 g/mol. The pharmaceutical hydrochloride salt has the formula C₂₃H₂₄N₄O₃·HCl and molecular weight approximately 440.92 g/mol. FDA's substance database identifies ozanimod and ozanimod hydrochloride as separate substance records, making correct salt-form identification important for API documentation and quality specifications.
PubChem lists ozanimod CAS 1306760-87-1, molecular formula C₂₃H₂₄N₄O₃ and molecular weight 404.5 g/mol. FDA separately lists ozanimod hydrochloride with the hydrochloride salt formula and molecular weight 440.92 g/mol.
Ozanimod is a sphingosine-1-phosphate receptor modulator with activity primarily at S1P₁ and S1P₅ receptors. Its pharmacological action reduces the circulation of specific lymphocyte populations by promoting functional antagonism and internalization of S1P₁ receptors. This limits migration of lymphocytes from lymphoid tissues into the circulation and consequently reduces the trafficking of activated immune cells into inflammatory tissues.
This mechanism is relevant to inflammatory neurological and gastrointestinal diseases because abnormal lymphocyte trafficking contributes to inflammatory processes in multiple sclerosis and ulcerative colitis. Ozanimod is therefore classified among immunomodulatory therapies rather than conventional cytotoxic immunosuppressants.
Ozanimod is approved for relapsing forms of multiple sclerosis, including clinically isolated syndrome, relapsing-remitting disease and active secondary progressive disease in adults. It is also indicated for moderately to severely active ulcerative colitis in adults.
The commercial drug product Zeposia contains ozanimod hydrochloride. FDA documentation describes capsules corresponding to 0.23 mg, 0.46 mg and 0.92 mg of ozanimod, equivalent to 0.25 mg, 0.5 mg and 1 mg of ozanimod hydrochloride, respectively.
Ozanimod is a chiral small molecule containing a substituted benzonitrile structure, a 1,2,4-oxadiazole ring and an indane-derived chiral center. PubChem identifies the active substance as the (S)-configured compound.
A reported melting-point value for ozanimod free base is approximately 134–137°C. This value should be treated as a reference physical property rather than automatically presented as a pharmaceutical release specification.
Ozanimod hydrochloride has also been investigated in multiple crystalline and amorphous solid-state forms. Patent literature describes distinct polymorphic forms and XRPD characteristics, demonstrating why solid-state form and polymorphic control can be important quality attributes for this API.
Ozanimod is a synthetic small-molecule API and can therefore be evaluated using conventional pharmaceutical analytical techniques such as HPLC/UPLC assay and related-substance analysis, residual-solvent testing, water determination, elemental impurity assessment and solid-state characterization.
Published analytical research has developed stability-indicating chromatographic methods for ozanimod and its related impurities. However, method-development acceptance criteria such as recovery, linearity, LOD and LOQ should not be confused with finished API release specifications. For example, an analytical method publication reports ozanimod assay recovery of approximately 99.2–101.3%, but this is method-validation performance and is not an API assay specification.
For commercial API manufacturing, the final specification should therefore be established against the applicable regulatory dossier, validated analytical methods and the exact ozanimod hydrochloride solid form being manufactured.
| Parameter | Specification |
|---|---|
| Appearance | white to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.0% – 102.0% |
| Loss on Drying | NMT 1.0% |
| Residue on Ignition | NMT 0.5% |
| Individual Impurity | NMT 0.5% |
| Total Impurities | NMT 1.0% |
| Water Content | NMT 1.0% |
| Melting Point | 134–137°C |