Can You Combine Provenge with Xofigo?

Clinical trials studying whether combining Provenge with Xofigo for castration-resistant prostate cancer leads to meaningful clinical outcomes are beginning to be planned.

According to Oliver Sartor, MD, medical director, Tulane Cancer Center, in a Onc Live interview, a small clinical trial will examine the effect of combining Provenge with Xofigo. Sartor stated the trial will be a proof of concept rather than a definitive treatment trial. The rationale is that the Xofigo will release antigens to make the cancer more immunologically accessible and potentially more likely to respond to Provenge.

Provenge and Xofigo

Xofigo is a radioactive injection used in the treatment of prostate cancer that has metastasized to bone and is resistant to medical or surgical therapies attempting to lower testosterone levels. It is the first radioactive drug for prostate cancer that has demonstrated an improvement in survival benefit while also being well tolerated by patients.

In the Phase III clinical trial leading to its approval, Xofigo plus standard of care demonstrated a 3.6 month overall survival benefit compared to standard of care alone—similar to other new drugs approved for castration-resistant prostate cancer.

Provenge is a recent option for the treatment of asymptomatic or minimally symptomatic, castration-resistant metastatic prostate cancer. This therapy is a vaccine that stimulates your body’s own immune system to attack and fight the spread of the prostate cancer.

Combining Provenge with Xofigo

In order to be considered a good candidate for Provenge, you need to have a rising PSA level despite standard anti-androgen treatments. Additionally, the cancer needs to have spread outside of the prostate, but not significant enough to need narcotics for pain control.

Oncology practice often involves the use of multiple drugs with different mechanisms of action in order to attempt to achieve a treatment benefit. Because immunotherapy like Provenge offers a different mechanistic action from Xofigo, there is interest in combining Provenge with Xofigo.

If you think that you might be a candidate for Provenge, Xofigo, or would like to consider combining Provenge with Xofigo you need to talk with your doctor. Because this combination has not been widely studied yet, your doctor may not have a lot of clinical evidence to discuss with you. Additionally, insurance companies tightly regulate the use of both Provenge and Xofigo. Your insurance company may require your doctor to follow a certain pathway or order in which cancer drugs are used.

Read more in our Prostate Cancer Health Center.

References

Kantoff PW et al. Sipuleucel-T immunotherapy for castration-resistant prostate cancer. New England Journal of Medicine 2010; 363:411-22.

Parker C et al. Overall survival benefit of radium-223 chloride (Alpharadin) in the treatment of patients with symptomatic bone metastases in castration-resistant prostate cancer (CRPC): a phase III randomized trial (ALSYMPCA). Eur J Cancer 47:Suppl 2, Sept 2011, p3.

Shore N et al. New developments in castrate-resistant prostate cancer. BJU International 2012 Jun; 109 Suppl 6:22-32