Understanding Sipuleucel-T for Prostate Cancer Treatment

Reprogramming your own body’s defenses to fight cancer might sound like something out of a science-fiction movie. Science has now made this reality, as researchers develop new ways to wrangle the disease. Sipuleucel-T (also known as Provenge) is a personalized cancer vaccine approved by the US Food and Drug Administration in 2010 to treat metastatic castration resistant prostate cancer, a difficult-to-treat advanced prostate cancer which no longer responds to hormone therapy. It should only be used for those with minimal or no symptoms. Around 4,000 patients rely on this treatment each year.

At its core, sipuleucel-T relies on taking your very own immune cells — dendritic cells, the watch guards responsible for sounding the panic alarms for an invasion — and training them to teach your own immune cells (T lymphocytes) to better recognize and kill tumor cells. Once upgraded, they are then injected into your body to stimulate your own anti-tumor immune responses.

The treatment consists of three rounds, each an hour long, delivered around every two weeks by intravenous infusion. A few days before each session, you will need to undergo extraction of the immune cells from your blood. They will then be processed to present cancer cell features to other immune cells in your body.

At this stage, it's critical to attend all appointments as scheduled, as the treatment cannot be stored for long. If you miss a treatment session, you would need to redo the cell extraction process. Half an hour before your treatment, you may be given acetaminophen (also known as Tylenol) and an antihistamine to minimize the chances of chills or fever. Following the treatment, you will need to be monitored for around 30 minutes in case of any severe reactions.

• Notably, while sipuleucel-T improves your chances of survival, it may not lower your prostate-specific antigen (PSA) levels, a marker in your blood used to monitor your prostate cancer.
• While unlikely, there is a chance of severe adverse reactions. If you have issues with breathing, chest pains, an irregular or racing heart rate, dizziness, nausea or vomiting, you should contact your doctor immediately. If you have pre-existing issues with your heart or lungs, you will need to be monitored closely throughout this treatment.
• If you get a fever over 100°F (37.7°C), redness or pain at the needle placement site, you should let your doctor know immediately, in case of infection.
• If there is difficulty accessing your veins during treatment, you may need a temporary central venous catheter. This is typically placed around your neck or chest, and helps access the bigger central veins of your body. It may be kept until your treatment schedule is over, to prevent the need for repeated needle pricks. If so, you would need to take care of the device, as keeping it clean and secure is critical to prevent infections.

Some commonly reported side effects that affect over 15% of people include:

• Chills
• Fatigue
• Pain (including back pain, joint aches or headaches)
• Fever
• Nausea

Generally, most side effects are manageable, with fevers and chills passing after two days. However, most will have a temporary inflammatory reaction after the infusion, which should be minimized by antihistamines given right before treatment. This reaction will fade within a few days.

Ultimately, sipuleucel-T will likely be well-tolerated, aside from temporary side effects, given its development from your very own cells. Unfortunately, its weaknesses include its high cost, and lengthy treatment process. However, it remains an active area of research and is currently being tested in combination with other treatments as well.