Trabectedin plus pegylated liposomal doxorubicin in the treatment of patients with partially platinum-sensitive ovarian cancer: current evidence and future perspectives

The effectiveness of platinum re-treatment in relapsed ovarian cancer depends on relapse-free/treatment-free intervals. Platinum agents can be effectively readministered to platinum-sensitive patients (relapsing >12 months after platinum), but efficacy is lower in partially platinum-sensitive (PPS) disease (relapsing 6-12 months after platinum). There is no clear standard treatment challenging PPS patients. Survival data in this subset with chemotherapy combinations such as pegylated liposomal doxorubicin (PLD) plus carboplatin or gemcitabine plus PLD are available from phase II trials ranging from 16 to 21 months. Recent results from OVA-301 phase III randomized trial evaluating trabectedin plus PLD showed the longest median overall survival ever reported in PPS patients (23 months). Subsequent chemotherapy (including platinum-based regimens) was administered later and survival in patients receiving third-line platinum was longer in patients treated with trabectedin plus PLD compared with those treated with PLD alone. These results suggest that prolonging platinum-free interval (PFI) with an effective non-platinum regimen improves outcome with subsequent third-line platinum treatment. An ongoing phase III trial (INOVATYON) aims to demonstrate if the results observed with trabectedin plus PLD in PPS patients are due to PFI extension, and if PFI extension with non-platinum combination prolongs response to subsequent platinum and survival in this population.

A journey under the sea: the quest for marine anti-cancer alkaloids

The alarming increase in the global cancer death toll has fueled the quest for new effective anti-tumor drugs thorough biological screening of both terrestrial and marine organisms. Several plant-derived alkaloids are leading drugs in the treatment of different types of cancer and many are now being tested in various phases of clinical trials. Recently, marine-derived alkaloids, isolated from aquatic fungi, cyanobacteria, sponges, algae, and tunicates, have been found to also exhibit various anti-cancer activities including anti-angiogenic, anti-proliferative, inhibition of topoisomerase activities and tubulin polymerization, and induction of apoptosis and cytotoxicity. Two tunicate-derived alkaloids, aplidin and trabectedin, offer promising drug profiles, and are currently in phase II clinical trials against several solid and hematologic tumors. This review sheds light on the rich array of anti-cancer alkaloids in the marine ecosystem and introduces the most investigated compounds and their mechanisms of action.