The Food and Drug Administration approved a once-daily HIV pill from Gilead that could help simplify care for some patients, the company announced Thursday.

The drug, marketed as Bixlenvo, is aimed at patients whose virus is already under control but who remain on complicated treatment regimens. It could also appeal to those who simply want to switch to a new treatment alternative.

The tablet combines bictegravir, the backbone of Gilead's blockbuster HIV pill Biktarvy, with lenacapavir, a first-in-class capsid inhibitor that has become a centerpiece of the company's long-term strategy for HIV treatment and prevention.

The approval makes the new pill the first single-tablet regimen available for adults with HIV whose virus is suppressed but are unable to use currently available one-pill treatment options, according to Gilead. That population accounts for an estimated 5% or more of individuals in the U.S. living with HIV, the company told CNBC.

The list price of the pill before discounts or rebates is $4,595 for a 30-day supply, which is in line with other daily single-tablet HIV treatments, Gilead told CNBC. People without health insurance may be eligible to get Bixlenvo for free through Gilead's patient assistance program, while those with commercial or private insurance may be able to receive co-pay support through another savings program, the company said.

"It fulfills an unmet need, particularly for individuals who are on complex regimens who just would not otherwise consolidate down to something really meaningful for them and prescribers," Dr. Jared Baeten, Gilead's clinical development and virology therapeutic area head, said in an interview ahead of the approval.

"But it's also meaningful for individuals who are seeking options for something new," he continued. "We want to build options that give people the opportunity to choose something that's going to work for them and work for them for the long haul."

There is no cure for HIV or AIDS. But many people living with HIV can manage the disease by taking a single pill daily, a treatment plan that Gilead helped pioneer two decades ago.

But some patients can't use any existing one-tablet options like Biktarvy and require more complex combinations of medicines because of drug resistance from older therapies, side effects or interactions with other drugs, among other treatment challenges. Those patients may have to take multiple pills a day and adhere to complicated dosing schedules.

Baeten said that group tends to be older and have long treatment histories, saying "some had to take handfuls of pills around 25 years ago." HIV also accelerates complications of aging, such as heart disease, diabetes and high cholesterol, in that age group, he added.

"It's incredibly meaningful to develop a medicine, in my perspective, for people aging with HIV," Baeten said.

The new pill is also aimed at people who are doing well on a single-tablet regimen, including Biktarvy, and want to switch to a new one. Baeten stressed that Bixlenvo does not aim to replace Biktarvy.

For patients already doing well on Biktarvy, the rationale for switching is more about expanding treatment choices, he said. He emphasized that HIV care is highly individualized and that long-term success often depends on finding a regimen that best fits a patient's preferences and lifestyle.

Baeten also said Bixlenvo is part of Gilead's broader effort to build a range of HIV treatment options around lenacapavir, including daily pills, weekly oral regimens and long-acting injectable therapies. The goal is to give patients flexibility to choose how they want to manage the disease, he said.

"We're going to build enough options that people can make the choice that's going to work for them," Baeten said. "Some people like the surety of once a day, and some people would want 'set it and forget it' once every six months."