Potential Process Control Issues with Pemetrexed.

Pemetrexed is a folate analog metabolic inhibitor used in treatment of locally advanced or metastatic nonsquamous non-small cell lung cancer and for mesothelioma. Intra-lot and inter-lot variability in the spectra of ALIMTA® was detected in the Drug Quality Study (DQS) using Fourier transform near-infrared spectrometry (FTNIR). One vial of 12 (8%) sampled from lot S20I013A appeared 3.0 multidimensional SDs from the other vials, suggesting that it represents a different material. Consequently, additional spectra from other lots were analyzed. Spectra of 147 vials from 23 lots in the spectral library contained 14 vials that were outside the main group (26.4 SDs using a subcluster detection test), suggesting that the 14 library vials (9.5% of the total) also contain differing materials.