Pegfilgrastim is a glycoprotein, with no hormonal effects of relevance for porphyrogenicity, and no effects on the mechanisms behind hepatic xenobiotic metabolism. However, side effects such as nausea may be potentially porphyrinogenic through reduction in caloric intake.

Pegfiligrastim is a covalent conjugate of filgrastim and monomethoxypolyethylene glycol (PEG).

Pegfiligrastim is used for reduction in the duration of neutropenia and the incidence of febrile neutropenia in patients treated with cytotoxic chemotherapy for malignancy and for mobilization of stemcells in cyclic or idiopatic neutropenia. It is given as an subcutaneous injection. Common adverse reactions of pegfilgrastim that can be confused with an acute porphyric attack are nausea and musculo-skeletal pain. Side effects such as nausea may be potentially porphyrinogenic through reduction in caloric intake.

Pegfilgrastim appears to be mainly eliminated by neutrophil mediated clearance, which becomes saturated at higher doses. Consistent with a self regulating clearance mechanism, the serum concentration of pegfilgrastim declines rapidly at the onset of neutrophil recovery.