Tamoxifen (TAM) is a non-steroidal estrogen receptor antagonist that enhances erlotinib (ERL)-inducedcytotoxicity in the treatment of NSCLC. ERL and TAM are metabolized by CYP3A4 enzymes. In addition,both drugs have the potential of altering the enzymatic activity through either inhibition (ERL) or induc-tion (TAM). Thus it was expected that pharmacokinetics (PK) drug–drug interactions (DDIs) could beencountered following their co-administration.
A new rapid and simple stability-indicating spectrofluorimetric method has been developed for the determination of two irreversible tyrosine kinase inhibitors (TKIs), neratinib (NER) and pelitinib (PEL). The method is based upon measurement of the native fluorescence intensity of both drugs at λex 270 nm in aqueous borate buffer solutions (pH 10.5). The fluorescence intensity