What is Vandetanib: Uses, Dosage, Side Effects and More

Vandetanib is a targeted cancer medication that blocks specific proteins that help cancer cells grow and spread. It's primarily used to treat a rare type of thyroid cancer called medullary thyroid carcinoma when surgery isn't possible or when the cancer has spread to other parts of the body.

This medication belongs to a class of drugs called tyrosine kinase inhibitors, which work like molecular scissors to cut off the signals that tell cancer cells to multiply. While it's a specialized treatment, understanding how it works and what to expect can help you feel more prepared if your doctor recommends it.

What is Vandetanib?

Vandetanib is a prescription cancer medication that targets specific proteins involved in cancer cell growth. It's what doctors call a "targeted therapy" because it focuses on particular molecules that cancer cells need to survive and multiply.

The medication comes as oral tablets that you take by mouth, making it more convenient than many cancer treatments that require hospital visits for infusion. It's also known by its brand name Caprelsa, and it represents a significant advance in treating certain types of thyroid cancer.

Unlike traditional chemotherapy that affects all rapidly dividing cells, vandetanib specifically targets cancer cells while leaving most healthy cells alone. This targeted approach often leads to fewer side effects than conventional cancer treatments.

What is Vandetanib Used For?

Vandetanib is primarily prescribed for treating medullary thyroid carcinoma, a rare type of thyroid cancer that accounts for about 3-4% of all thyroid cancers. Your doctor will typically recommend it when the cancer is advanced or has spread to other parts of your body.

This medication is specifically approved for patients whose tumors cannot be removed surgically or whose cancer has metastasized (spread) to distant parts of the body. It's particularly helpful for people with hereditary forms of medullary thyroid carcinoma caused by genetic mutations.

Sometimes doctors may prescribe vandetanib for other rare cancers as part of clinical trials or compassionate use programs. However, its primary and most well-studied use remains in treating advanced medullary thyroid carcinoma when other treatments aren't suitable.

How Does Vandetanib Work?

Vandetanib works by blocking multiple proteins that cancer cells use to grow, spread, and form new blood vessels. Think of it as putting up roadblocks on several highways that cancer cells travel to multiply and spread throughout your body.

The medication specifically targets proteins called RET, VEGFR, and EGFR, which are like switches that tell cancer cells to grow and divide. By blocking these switches, vandetanib can slow down or stop the cancer's progression.

This is considered a moderately strong cancer medication. While it's not as intensive as some chemotherapy drugs, it's still powerful enough to significantly impact cancer growth. The targeted approach means it's generally more tolerable than traditional chemotherapy, though it still requires careful monitoring by your healthcare team.

How Should I Take Vandetanib?

Take vandetanib exactly as your doctor prescribes, usually once daily at the same time each day. You can take it with or without food, but try to be consistent with your choice to help maintain steady levels in your body.

Swallow the tablets whole with a full glass of water. Don't crush, break, or chew them, as this can affect how the medication is absorbed. If you have trouble swallowing tablets, talk to your doctor about alternatives.

It's best to take vandetanib on an empty stomach if possible, as food can sometimes reduce how well your body absorbs the medication. However, if you experience stomach upset, your doctor may recommend taking it with a light meal or snack.

Avoid grapefruit and grapefruit juice while taking this medication, as they can increase the levels of vandetanib in your blood and potentially cause more side effects. Also, try to take it at least 2 hours before or after calcium supplements or antacids.

How Long Should I Take Vandetanib For?

You'll typically continue taking vandetanib for as long as it's controlling your cancer and you're tolerating it well. This often means taking it long-term, sometimes for months or even years, depending on how your cancer responds.

Your doctor will monitor your response through regular scans and blood tests, usually every few months. If the cancer stops responding to the medication or if you develop serious side effects, your doctor may adjust the dose or consider switching to a different treatment.

The duration of treatment varies greatly from person to person. Some people take it for several years with good results, while others may need to stop sooner due to side effects or cancer progression. Your healthcare team will work with you to find the right balance between controlling your cancer and maintaining your quality of life.

What Are the Side Effects of Vandetanib?

Like all cancer medications, vandetanib can cause side effects, though not everyone experiences them. Most side effects are manageable with proper medical care and monitoring.

Here are the most common side effects you might experience:

• Diarrhea, which affects about 60% of people taking this medication
• Skin rash or acne-like bumps on your face and upper body
• High blood pressure that requires regular monitoring
• Nausea and decreased appetite
• Fatigue and weakness
• Headaches
• Changes in your fingernails and toenails

These common side effects are usually mild to moderate and often improve as your body adjusts to the medication. Your doctor can prescribe medications to help manage symptoms like diarrhea and nausea.

More serious but less common side effects include heart rhythm changes, severe skin reactions, and liver problems. Your doctor will monitor you closely with regular blood tests and heart rhythm checks to catch any serious issues early.

Very rarely, some people may experience severe lung problems, severe bleeding, or a condition called tumor lysis syndrome where cancer cells break down too quickly. While these are uncommon, it's important to report any unusual symptoms to your healthcare team immediately.

Who Should Not Take Vandetanib?

Vandetanib isn't suitable for everyone, and your doctor will carefully review your medical history before prescribing it. People with certain heart conditions, particularly those with a history of irregular heart rhythms, may not be good candidates for this medication.

You should not take vandetanib if you're pregnant or breastfeeding, as it can harm an unborn baby or nursing infant. Women of childbearing age need to use effective birth control during treatment and for several months after stopping the medication.

People with severe liver or kidney problems may need dose adjustments or might not be able to take this medication safely. Your doctor will check your liver and kidney function before starting treatment and monitor them regularly.

If you have a history of bleeding disorders, recent surgeries, or are taking blood-thinning medications, your doctor will need to carefully weigh the risks and benefits. Additionally, people with certain genetic conditions that affect heart rhythm may not be suitable candidates.

Vandetanib Brand Name

Vandetanib is sold under the brand name Caprelsa. This is the only brand name available for this medication, as it's manufactured by AstraZeneca pharmaceuticals.

You might see both names used interchangeably in medical literature and prescriptions. Whether your prescription says "vandetanib" or "Caprelsa," it's the same medication with the same active ingredient and effects.

Generic versions of vandetanib are not yet widely available in many countries, so most people receive the brand-name Caprelsa. Your insurance coverage and pharmacy will determine which version you receive, though the medication itself remains the same.

Vandetanib Alternatives

If vandetanib isn't suitable for you or stops working effectively, several alternative treatments are available for medullary thyroid carcinoma. Your doctor will consider your specific situation when recommending alternatives.

Cabozantinib is another targeted therapy that works similarly to vandetanib and is often used as an alternative. It targets some of the same proteins but may work better for certain people or have a different side effect profile.

Other alternatives include traditional chemotherapy drugs, radiation therapy, or participation in clinical trials testing newer targeted therapies. The best alternative depends on factors like your overall health, how your cancer has responded to previous treatments, and your personal preferences.

Sometimes doctors might recommend a combination of treatments or suggest taking a break from medication to let your body recover before trying a different approach. The key is working closely with your oncology team to find the most effective treatment plan for your specific situation.

Is Vandetanib Better Than Cabozantinib?

Both vandetanib and cabozantinib are effective treatments for medullary thyroid carcinoma, but there's no clear winner that works better for everyone. The choice between them often depends on your individual circumstances and how you respond to each medication.

Studies suggest that cabozantinib might be slightly more effective at shrinking tumors and delaying cancer progression, but it can also cause more severe side effects in some people. Vandetanib tends to be better tolerated by many patients, especially regarding digestive side effects.

Your doctor will consider factors like your overall health, other medications you're taking, and your specific type of thyroid cancer when choosing between these options. Some people do better with one medication than the other, and it's not always possible to predict which will work best for you.

The good news is that having both options available gives you and your doctor flexibility in treatment planning. If one doesn't work well or causes troublesome side effects, you can often switch to the other.