In 2006, bortezomib, a proteasome inhibitor, was approved for the treatment of patients with refractory or relapsed multiple myeloma.
In the domestic clinical trial on bortezomib, which was limited in scale, therapy with it caused serious adverse effects such as interstitial pneumonia and acute lung injuries. Thus, in order to determine whether bortezomib is safe and effective, we investigated its adverse effects during the treatment period and compared them with those described in the bortezomib interview form. We investigated the reasons for extension of interval and discontinuation. Administration of this medicine resulted in adverse effects such as peripheral neuropathies and decrease in the platelet count that were dose-limiting factors. Furthermore, as bortezomib is a substrate for CYP3A4, we investigated its interaction with itraconazole.
The reasons for extension of interval and discontinuation were mainly studied (87 % of the investigation). In particular, a remarkable decrease in the platelet count and a high incidence of peripheral neuropathy of grade 3 or higher were noted, making continuation of the treatment difficult. Further, combination therapy with bortezomib and itraconazole significantly increased the incidence of peripheral neuropathy. This suggests that caution is needed when combining bortezomib and itraconazole.
