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

Mavorixafor is a prescription medication that helps people with a rare immune system disorder called WHIM syndrome. This condition makes it hard for your body to fight off infections because certain white blood cells get trapped in your bone marrow instead of circulating through your bloodstream where they're needed.

If you or someone you care about has been diagnosed with WHIM syndrome, you might feel overwhelmed by all the medical information. Let's walk through what mavorixafor does, how it works, and what you can expect when taking this medication.

What is Mavorixafor?

Mavorixafor is the first and only FDA-approved treatment specifically designed for WHIM syndrome. It belongs to a class of medications called CXCR4 antagonists, which work by blocking certain chemical signals in your body.

The medication comes as oral tablets that you take by mouth. It was approved by the FDA in 2024 after clinical trials showed it could help increase the number of infection-fighting white blood cells in people with WHIM syndrome.

WHIM syndrome affects fewer than 100 people worldwide, making mavorixafor what doctors call an "orphan drug" - a medication developed for very rare conditions. The drug is also known by its brand name Xolremdi.

What is Mavorixafor Used For?

Mavorixafor treats WHIM syndrome, a rare genetic condition that affects your immune system. WHIM stands for warts, hypogammaglobulinemia (low antibodies), infections, and myelokathexis (white blood cells stuck in bone marrow).

People with WHIM syndrome typically experience frequent infections because their neutrophils - important white blood cells that fight bacteria - can't leave the bone marrow properly. This leaves them vulnerable to respiratory infections, skin infections, and other bacterial illnesses.

The medication helps release these trapped white blood cells so they can circulate throughout your body and do their job of fighting infections. Clinical studies showed that people taking mavorixafor had fewer severe infections and improved quality of life.

How Does Mavorixafor Work?

Mavorixafor works by blocking CXCR4 receptors in your bone marrow. These receptors normally keep white blood cells from leaving the bone marrow, but in WHIM syndrome, they work too well and trap too many cells.

Think of it like unlocking a door that's been stuck. The medication essentially "unlocks" the white blood cells so they can leave the bone marrow and travel through your bloodstream to fight infections wherever they're needed.

This is considered a targeted therapy because it specifically addresses the root cause of WHIM syndrome rather than just treating symptoms. The effect is relatively quick - studies showed increased white blood cell counts within hours of taking the medication.

How Should I Take Mavorixafor?

Take mavorixafor exactly as your doctor prescribes, typically once daily with or without food. Swallow the tablets whole with a glass of water - don't crush, chew, or break them.

Your doctor will likely start you on a specific dose based on your weight and medical condition. They may adjust this dose over time depending on how well you respond to treatment and any side effects you experience.

It's important to take mavorixafor at the same time each day to maintain steady levels in your bloodstream. Set a daily alarm or use a pill organizer to help you remember. If you're taking other medications, let your doctor know as some drugs can interact with mavorixafor.

Before starting treatment, your doctor will run blood tests to check your white blood cell counts and liver function. They'll continue monitoring these levels regularly while you're taking the medication.

How Long Should I Take Mavorixafor For?

Most people with WHIM syndrome will need to take mavorixafor long-term, potentially for life. This is because WHIM syndrome is a genetic condition that doesn't go away on its own.

Your doctor will monitor your response to treatment through regular blood tests and checkups. They'll look at your white blood cell counts, how often you get infections, and your overall quality of life to determine if the medication is working effectively.

Never stop taking mavorixafor suddenly without talking to your doctor first. Your white blood cell counts could drop quickly, leaving you more vulnerable to infections. If you need to stop the medication for any reason, your doctor will help you do so safely.

What Are the Side Effects of Mavorixafor?

Like all medications, mavorixafor can cause side effects, though not everyone experiences them. Most side effects are mild to moderate and tend to improve as your body adjusts to the medication.

Here are the most common side effects you might experience:

• Nausea and stomach upset
• Headaches
• Dizziness
• Fatigue or feeling tired
• Diarrhea
• Upper respiratory tract infections

These side effects usually occur within the first few weeks of treatment and often become less bothersome over time. Taking the medication with food can help reduce stomach-related side effects.

Some people may experience more serious side effects that require immediate medical attention. While these are less common, it's important to know what to watch for:

• Severe allergic reactions (rash, swelling, difficulty breathing)
• Unusual bleeding or bruising
• Signs of liver problems (yellowing of skin or eyes, dark urine, severe stomach pain)
• Severe or persistent nausea and vomiting
• Changes in heart rhythm

Contact your doctor right away if you experience any of these serious side effects. They can help determine if the symptoms are related to mavorixafor and adjust your treatment if needed.

Who Should Not Take Mavorixafor?

Mavorixafor isn't suitable for everyone. Your doctor will carefully review your medical history before prescribing this medication to make sure it's safe for you.

You should not take mavorixafor if you're allergic to the medication or any of its ingredients. Tell your doctor about any previous allergic reactions to medications, especially if you've experienced serious symptoms like difficulty breathing or swelling.

People with severe liver disease may not be able to take mavorixafor safely. The medication is processed by your liver, so if your liver isn't working well, the drug could build up to dangerous levels in your body.

Pregnant or breastfeeding women should discuss the risks and benefits with their doctor. There isn't enough research yet to know if mavorixafor is safe during pregnancy or if it passes into breast milk.

Children and teenagers under 18 haven't been studied extensively with mavorixafor. Your doctor will weigh the potential benefits against unknown risks if considering this medication for a younger patient.

Mavorixafor Brand Name

Mavorixafor is sold under the brand name Xolremdi. This is the commercial name you'll see on your prescription bottle and pharmacy labels.

The medication is manufactured by X4 Pharmaceuticals, a company that specializes in developing treatments for rare diseases. Xolremdi is currently the only brand name available for mavorixafor.

Since this is a relatively new medication for a rare condition, generic versions aren't yet available. Your insurance coverage and pharmacy options may be limited, so work closely with your healthcare team to access the medication.

Mavorixafor Alternatives

Currently, there are no other medications specifically approved to treat WHIM syndrome. Mavorixafor is the first and only targeted treatment for this rare condition.

Before mavorixafor was available, doctors managed WHIM syndrome symptoms with supportive care. This might include antibiotics to treat infections, immunoglobulin replacement therapy to boost antibody levels, and growth factors to stimulate white blood cell production.

Some people with WHIM syndrome may still need these supportive treatments alongside mavorixafor. Your doctor will create a comprehensive treatment plan that addresses all aspects of your condition.

Researchers are continuing to study other potential treatments for WHIM syndrome, but these are still in early development stages. For now, mavorixafor represents the most targeted and effective treatment available.

Is Mavorixafor Better Than Other CXCR4 Antagonists?

Mavorixafor is specifically designed and approved for WHIM syndrome, while other CXCR4 antagonists like plerixafor are used for different purposes. Plerixafor is mainly used to help mobilize stem cells for transplant procedures.

The key difference is that mavorixafor is formulated for daily oral use over long periods, while plerixafor is given as injections for short-term use. Mavorixafor also has a longer duration of action, making it more suitable for chronic treatment.

Clinical trials specifically tested mavorixafor in people with WHIM syndrome, showing it effectively increases white blood cell counts and reduces infection rates. Other CXCR4 antagonists haven't been studied extensively in this patient population.

Your doctor will choose the right medication based on your specific condition and treatment goals. For WHIM syndrome, mavorixafor is currently the most appropriate choice.