- Generic Name – Lenacapavir
- Brand Name – Sunlenca
- Category – Capsid inhibitor (a new class of HIV drugs)
- Dosage Forms – Oral tablets & Subcutaneous Lenacapavir injections are available for use.
- Manufacturer – Gilead Sciences .
Table of Contents
What is Lenacapavir injection?
Lenacapavir is long acting anti- retroviral drug approved by Food And Drug Administration (FDA) for prevention of HIV/AIDS disease on 18 June 2025.Lenacapavir injection or tablet used for adult who does not gives respond to many other drug used for HIV infection . This drug mainly effective for HIV-1 infection.
It’s belonging to class first in class capsid inhibitor. The drug acts by targeting single part of virus i.e. the capsid protein & interfere multiple stages of virus such as virus assembly, disassembly and transport.
Lenacapavir drug manufactured by Gilead Sciences. It is long acting formulation and only needs twice Lenacapavir injection per year after loading dose which is more convenient for HIV patient.
Mechanism of Action of Lenacapavir injection :
Lenacapavir injection targets the HIV-1 capsid protein i.e. p24 which is responsible for formation of conical shell of the viral core. This medication directly interfere the multiple stages of the HIV replication cycle.
Let’s see, how Lenacapavir affects different stages of the HIV life cycle.
1.Inhibition of Viral Uncoating ( Early stage ) –
The viral capsid release its RNA for reverse transcription after entering HIV into host cell. Lenacapavir binds to specific site of capsid and stabilize the structure which leads to prevention of proper uncoating . As results , the virus fails to release its genetic material, halting replication early.
2.Disruption of Nuclear Import –
The HIV capsid must interact with cellular transport proteins, such as CPSF6, in order to enter the nucleus and cause infection. By binding to the interface between capsid hexamers, Lenacapavir interferes with these interactions, preventing the viral core from properly trafficking into the nucleus and blocking integration into the host genome.
3.Inhibition of Viral Assembly and Maturation (Late Stage) –
In addition to early-stage inhibition , Lenacapavir also impacts the assembly of new virions in infected cells. During the assembly process, it hinders the appropriate development of the capsid shell around the viral RNA and enzymes, causing the release of immature, non-infectious virus particles.
Uses :
Lenacapavir is used to treat HIV-1 infection, especially in individuals who have received a lot of treatment and are resistant to several antiretroviral medications. It is administered in conjunction with other antiretroviral medications (ART).
- Treatment of adult HIV-1 infection that is resistant to many drugs.
- Employed when resistance becomes other HIV medicines ineffective.
- Used in conjunction with additional antiretroviral medications to inhibit the virus.
- Perfect for individuals who require a long-acting therapy option—it is administered as a subcutaneous injection once every six months following the initial oral and injection loading dose.
Dosage :
This medicine is taken in two steps:
Step 1: Tablets (for the first few days)
Step 2: Injections (every 6 months)
Step 1–
- Day 1: Take 2 tablets (each 300 mg) by mouth
- Day 2: Take 2 tablets again (each 300 mg) by mouth
- Day 8: Take 1 tablet (300 mg) by mouth
Step 2–
- Get 1 injection under the skin (dose: 927 mg)
- You will need only 1 injection every 6 months (twice a year).
Route of Administration :
Lenacapavir drug administered by oral route and injection gives in persons arm, thigh or stomach .
Side Effects :
1.Common Side Effects –
| Side Effect | Description |
|---|---|
| Injection site reactions | Pain, redness, swelling, or a lump where the injection is given (most common side effect) |
| Nausea | Feeling of sickness in the stomach |
| Diarrhea | Frequent loose stools |
| Headache | Mild to moderate headaches |
| Tiredness (fatigue) | Feeling weak or low on energy |
| Loss of appetite | Reduced desire to eat |
2.Less Common but Serious Side Effects –
| Side Effect | Description |
|---|---|
| Liver problems | Elevated liver enzymes, yellowing of skin or eyes (jaundice), dark urine, or upper right abdominal pain—requires medical attention |
| Immune Reconstitution Inflammatory Syndrome (IRIS) | As the immune system gets stronger, it may overreact to hidden infections in the body |
| Allergic reactions (rare) | Rash, itching, swelling, dizziness, or trouble breathing (requires emergency help) |
Precaution :
To ensure safety and efficacy, the following measures should be done before starting Lenacapavir (Sunlenca):
1.Use Under Specialist Care Only –
- Lenacapavir should only be used under the supervision of an HIV specialist.
- It must never be taken by alone; it must always be taken in addition other antiretroviral medications.
2. Liver Problems –
- Patients with existing liver disease (like hepatitis B or C) should be monitored closely, as Lenacapavir can affect liver function.
- Liver function tests are often required before and during treatment.
3.Pregnancy and Breastfeeding –
- Limited information is available on use during pregnancy.
- Women who are pregnant or breastfeeding should consult their doctor before using this medicine.
4.Injection Site Care –
The drug is given by injection under the skin, monitor the injection site for pain, swelling, or lumps.
5.Immune Reconstitution Syndrome (IRIS) –
In people with very low immune function, Lenacapavir may cause the immune system to react strongly to hidden infections.
Drug Interactions :
The body uses enzymes, particularly CYP3A and P-gp transporters, to break down lenacapavir. Certain medications have the ability to alter their level in the body, which can impact their effectiveness or raise adverse effects.
1.Drugs to Avoid (Strong CYP3A Inducers)-
These can reduce the effect of Lenacapavir by speeding up its breakdown
| Drug Name | Common Use |
|---|---|
| Rifampin | Tuberculosis |
| Phenytoin | Seizures |
| Carbamazepine | Epilepsy |
| St. John’s Wort | Herbal antidepressant |
2.Drugs That Need Caution or Dose Adjustment–
| Drug Type | Examples | Note |
|---|---|---|
| Anticonvulsants | Phenobarbital, Phenytoin | May lower Lenacapavir level |
| Antifungals | Ketoconazole, Itraconazole | May increase Lenacapavir level |
| Antiretroviral | Other HIV meds | Some may interact; must be selected carefully |
| Oral contraceptives | Ethinyl estradiol-based pills | Limited data—alternative contraception may be advised |
Patient Tips:–
Ø Always inform your doctor about all medications, supplements, or herbal products you take.
Ø Never start or stop any drug without your doctor’s advice during Lenacapavir treatment.
Ø Avoid alcohol and unnecessary herbal products during therapy.
Conclusion :
An innovative development in HIV treatment, lenacapavir (Sunlenca) gives patients with multidrug-resistant HIV-1 infection hope. Unlike conventional antiretroviral medications, it targets several stages of the HIV lifecycle through its distinct mechanism of action as a capsid inhibitor.
It enhances patient adherence and treatment convenience with its long-acting formulation, which requires only two injections yearly following the initial oral dosages. It does, however, have possible side effects that require certain safety measures, and may interact with other medications, just like any other medication. It should therefore always be used in combination with other HIV medications and under supervision from a physician.
Lenacapavir represents a major step forward in managing HIV, especially for those who have limited treatment options. Staying informed about its use, safety, and drug interactions is essential for both patients and healthcare providers.
Nice article.