Treatment Options - Zolinza
What is Zolinza?
Zolinza (vorinostat) is a histone deacetylase (HDAC) inhibitor. Some cancer cells display excess HDAC activity, which affects cell growth. In laboratory studies, Zolinza has been shown to inhibit cancer cell growth and to induce cell death.
Zolinza is made by Merck and is FDA approved for the treatment of another cancer, a type of lymphoma. Other names for Zolinza are SAHA (suberoylanilide hydroxamic acid) and MK0683. Zolinza is an oral drug that is taken once a day with food.
Merck is no longer pursuing an FDA indication in multiple myeloma. However, since Zolinza is FDA-approved for another cancer, doctors may prescribe it off-label for myeloma based on the data supporting its effectiveness. In addition, researchers are continuing to evaluate Zolinza in combination with various myeloma agents in clinical trials, so patients may receive Zolinza as part of a clinical trial.
The Multiple Myeloma Research Consortium has supported the development of Zolinza in multiple myeloma and participated in a phase II trial demonstrating its utility.
What do we know about Zolinza’s effectiveness in myeloma?
Adding Zolinza to Velcade (bortezomib), Revlimid (lenalidomide), or Thalomid (thalidomide) has resulted in responses in relapsed/refractory myeloma.
The combination of Zolinza and Velcade provided higher response rates, but not clinically significant improvement in disease progression or survival, compared to Velcade alone in a Phase III trial.
- This trial included 637 patients who had received an average of 2 previous therapies.
- The overall response rate seen with Zolinza and Velcade was significantly higher than that seen with Velcade alone (56% vs. 41%).
- Combination therapy with Zolinza and Velcade significantly prolonged average time without myeloma disease progression compared with Velcade alone (7.6 months versus 6.8 months). However, this difference is relatively small.
- At the current time, there is no difference in survival between the two treatment groups.
- The most common severe side effects seen in both study arms included low blood cell and platelet counts, diarrhea, and fatigue.
Based on these results and those of an earlier trial that showed an improved overall response rate with Zolinza and Velcade compared with Velcade alone, this combination is now listed as a treatment option for relapsed/refractory myeloma in myeloma treatment guidelines.
Zolinza has also been evaluated as part of combination therapy in newly diagnosed myeloma.
- Results of a Phase I trial that added Zolinza to Revlimid, Velcade and dexamethasone are promising. Ninety-seven percent of the 30 patients enrolled in the study responded to therapy, with 30% achieving a stringent complete response and 10% achieving a complete response or near complete response. No unexpected side effects were noted.
How is Zolinza currently being studied in myeloma?
Zolinza is being studied in a number of clinical trials in relapsed and/or refractory myeloma, including:
- A Phase I/II trial in combination with Revlimid and dexamethasone (RZD) in patients who are no longer responding to Revlimid
- A Phase I/II trial in combination with Kyprolis (carfilzomib), Revlimid, and dexamethasone (QUAD)
- A Phase II trial in combination with Velcade, which has completed enrollment
- A Phase I trial in combination with Revlimid, which has completed enrollment