Lenacapavir is used with other HIV medications to help control HIV infection. It helps to decrease the amount of HIV in your body so your immune system can work better. This lowers your chance of getting HIV complications (such as new infections, cancer) and improves your quality of life. Lenacapavir belongs to a class of drugs known as capsid inhibitors. It blocks the virus from growing and infecting more cells.

Lenacapavir is not a cure for HIV infection. To decrease your risk of spreading HIV disease to others, continue to take all HIV medications exactly as prescribed by your doctor. Use an effective barrier method (latex or polyurethane condoms/dental dams) during sexual activity as directed by your doctor. Do not share personal items (such as needles/syringes, toothbrushes, and razors) that may have contacted blood or other body fluids. Consult your doctor or pharmacist for more details.

Read the Patient Information Leaflet if available from your pharmacist before you start using lenacapavir and each time you get a refill. If you have any questions, ask your doctor or pharmacist.

Take this medication by mouth with or without food as directed by your doctor. This form of lenacapavir is used at the beginning of treatment for 2 or 3 doses, before starting treatment with the injectable form given under the skin. After you start treatment with the injectable form, this form may also be used if you miss or will miss a planned injection. Follow your doctor's instructions carefully on when to take the tablet form of lenacapavir and when to get your injection of lenacapavir.

Nausea may occur. If this effect lasts or gets worse, tell your doctor or pharmacist promptly.

Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

As your immune system gets stronger, it can begin to fight off infections you already had, possibly causing disease symptoms to come back. You could also have symptoms if your immune system becomes overactive. This reaction may happen at any time (soon after starting HIV treatment or many months later). Get medical help right away if you have any serious symptoms, including:

• unexplained weight loss
• severe tiredness
• muscle aches/weakness that doesn't go away
• headaches that are severe or don't go away
• joint pain
• numbness/tingling of the hands/feet/arms/legs
• vision changes
• signs of infection (such as fever, chills, swollen lymph nodes, trouble breathing, cough, non-healing skin sores)
• signs of an overactive thyroid (such as irritability, nervousness, heat intolerance, fast/pounding/irregular heartbeat, bulging eyes, unusual growth in the neck/thyroid known as a goiter)
• signs of a certain nerve problem known as Guillain-Barre syndrome (such as unsteadiness, loss of coordination, trouble swallowing/speaking/chewing, trouble moving your eyes)
• signs of liver disease (such as nausea/vomiting that doesn't stop, loss of appetite, stomach/abdominal pain, yellowing eyes/skin, dark urine)

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:

• rash
• itching/swelling (especially of the face/tongue/throat)
• severe dizziness
• trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Before taking lenacapavir, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history.

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

During pregnancy, this medication should be used only when clearly needed. Treatment can lower the risk of passing HIV infection to your baby, and lenacapavir may be part of that treatment. Discuss the risks and benefits with your doctor.

It is unknown if this medication passes into breast milk. Because breast milk may transmit HIV, consult your doctor before breastfeeding.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Other medications can affect the removal of lenacapavir from your body, which may affect how lenacapavir works. Examples include certain other HIV drugs (such as atazanavir/cobicistat, atazanavir/ritonavir, efavirenz, nevirapine, tipranavir/ritonavir), rifamycins (such as rifampin, rifabutin), certain drugs used to treat seizures (such as carbamazepine, oxcarbazepine, phenobarbital, phenytoin), St. John's wort, among others.

This medication can slow down the removal of other medications from your body, which may affect how they work. Examples of affected drugs include asunaprevir, elacestrant, ergot drugs (such as dihydroergotamine, ergotamine), flibanserin, lomitapide, rivaroxaban, among others.

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call 1-800-222-1222. Canada residents can call 1-844-764-7669.

Do not share this medication with others.

Lab and/or medical tests (such as viral load, T-cell counts) should be done while you are taking this medication. Keep all medical and lab appointments. Consult your doctor for more details.

It is important to take each dose of this medication as scheduled. If you miss a dose, ask your doctor or pharmacist right away for a new dosing schedule. Do not double the dose to catch up.

Store in the original bottle at room temperature away from light and moisture. Do not store in the bathroom. Keep the drying agent (desiccant) in the bottle. Tightly close the bottle when not in use. If your tablets are in a blister package, keep the medication in the blister package until ready to use. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.