Development and validation of an HPLC-MS/MS method to simultaneously quantify brigatinib, lorlatinib, pralsetinib and selpercatinib in human K2-EDTA plasma

A liquid chromatography–tandem mass spectrometry method was developed and validated to quantify the small-molecule inhibitors (SMIs) brigatinib, lorlatinib, pralsetinib and selpercatinib, which are used in patients with oncogenic-driven non-small cell lung cancer. Chromatographic separation was performed on a HyPURITY® C ₁₈ analytical column with a gradient elution using ammonium acetate in water and in methanol, both acidified with formic acid 0,1%. Detection and quantification were performed using a triple quad mass spectrometer with an electrospray ionization interface. The assay was validated over a linear range of 50–2,500 ng/ml for brigatinib, 25–1,000 ng/ml for lorlatinib, 100–10,000 ng/ml for pralsetinib and 50–5,000 ng/ml for selpercatinib. All four SMIs were stable for at least 7 days under cool conditions (2–8°C), and at least 24 h at room temperature (15–25°C) in K2-EDTA plasma. Under freezing conditions (−20°C), all SMIs were stable for at least 30 days, except for the lowest quality control (QC _LOW) of pralsetinib. The QC _LOW of pralsetinib was stable for at least 7 days at −20°C. This method provides an efficient and simple way to quantify four SMIs with a single assay in clinical practice.