endTB-Q: what if curing the most resistant tuberculosis took less than a year?

Elvis Espinosa is fascinated by music. Above all, the huaynos of his native La Oroya, a mining town nestled more than three thousand meters above sea level in the department of Junín, where he lived until two decades ago, before migrating to Lima in search of a more stable future. In his house in the Carabayllo district, north of the capital, he keeps an alto saxophone. Sometimes, he sits next to his eldest son - now sixteen - and plucks a few notes from it, more for the intimate pleasure of remembering than for the precision of the melody.

But just four years ago, holding that saxophone was an impossible, almost unthinkable gesture.

In 2021, during the last stage of the pandemic, Espinosa had overcome a case of COVID-19, although the lingering symptoms made him uneasy. “I kept coughing harder, I started leaking blood, and then I went to a medical post,” he recalls. The diagnosis came with the forcefulness of a thud: tuberculosis.

It was not the most common form of the disease. At social security, they explained to him that he was facing a variant resistant to first-line drugs, known as multidrug-resistant (MDR-TB). Treatment consisted of a routine of up to 16 pills a day accompanied by painful injections that, despite their rigor, brought no relief.

Despite the visible physical wear and tear, Espinosa says that the feeling of uselessness was what sunk him the most: unable to work, with no income to support his wife and two children, with a recently acquired plot of land where he dreamed of building his house that had become an unpayable debt, depression began to dominate his life.

“I was like this for a year. According to me, I was getting better, but four, five, six months would go by, and nothing, I was still dropping blood, there was no recovery,” she recalls.

In December of that year, he traveled with his family to La Oroya. He thought that would be his last return to the place where he was born. “I thought I was going somewhere else,” he says. It was no wonder: the social security had confirmed that his disease had evolved into an even more complex form, pre-XDR tuberculosis (pre-XDR TB), resistant to several of the usual drugs and much more difficult to treat.

Nothing seemed to bode well for improvement. Until clinical research, implemented in Peru by Socios En Salud, came knocking on his door.

From the lab to the neighborhood: How endTB-Q was born

In clinical terms, pre-XDR-TB is defined as rifampicin-resistant (RR) or multidrug-resistant (MDR) TB, which also exhibits resistance to fluoroquinolones, broad-spectrum antibiotics. “This combination offered fewer treatment options,” says Dr. Jimena Ruiz, coordinator of the Clinical Trials Unit (UNEC) at Socios En Salud.

“Previously it was thought that resistance only appeared due to non-compliance with treatment, but today we know that someone can be directly infected with a resistant form,” she adds. All this makes pre-XDR TB a more complex form to treat than RR/MDR TB, which still offers better cure rates.

On a global level, the magnitude is clear: in 2023, the World Health Organization (WHO) estimated 10 million new cases of tuberculosis, of which nearly 100,000 corresponded to pre-XDR. In Peru, that same year some 1,424 cases of multidrug-resistant tuberculosis were registered. Within them, the pre-XDR fraction is smaller, but especially critical, as it forces treatments of up to 18 months with potent drugs and constant monitoring.

How to reduce this burden and offer better alternatives? The answer came from endTB, an international consortium led by Partners In Health, Interactive Research and Development and Médecins Sans Frontières, and funded by Unitaid, which for more than ten years has been working on the development of less toxic and faster therapies against resistant forms of the disease. In 2021, that effort materialized in the endTB-Q clinical trial, designed specifically to tackle pre-XDR TB.

The research recruited 324 participants from six countries, including Peru, which contributed 6% of the total. The start was not easy: recruitment coincided with the COVID-19 pandemic, when many health centers were closed or did not diagnose in time. Even so, Socios En Salud managed to implement the study in the Hipólito Unanue and Sergio Bernales national hospitals, after overcoming a complex regulatory process that included approval from ethics committees, clearance from the National Health Institute (INS), drug importation and coordination with DIRIS and local facilities.

“The experience was intense. Patients arrived in very serious conditions and we had to accompany them for two years in a context of fear and uncertainty,” Dr. Ruiz recalls. “When we started, the treatments were long, with injectables and hospitalizations; today we talk about shorter and totally oral schemes.”

When we started, the treatments were long, with injectables and hospitalizations; today we talk about shorter and totally oral schemes.

A response in the midst of a pandemic

That same year, at the most critical point of his illness, Espinosa was invited to participate in the endTB-Q by the UNEC team, which toured health centers, checked tuberculosis admission books and, when it found someone who met the criteria, arranged for their transfer. Because of his proximity to the Comas district, he was referred to the Sergio Bernales National Hospital.

“They told me that they would support me with the medicines, that they would take them home, that I would no longer have to go to the post or spend money on fares. Socios En Salud gave me mobility for appointments and support vouchers. The treatment lasted a year, but it was all pills, no vials,” she says.

The support, however, went beyond the clinical. In the midst of debts and depression that the disease had exacerbated, Espinosa received psychological and social support. “My self-esteem had been lowered because not everyone has this disease. We’re looked down on (…) Socios En Salud supported me with a psychologist,” she says.

For Dr. Ruiz, this accompaniment managed by the team of professionals and community health agents made the difference. “It’s something that sets Socios En Salud apart: we apply the same comprehensive support approach in clinical trials as we do in our community programs,” she says.

Espinosa felt it in her own body: unlike the treatment she received early in her illness, she now took only four pills a day, went through monthly checkups and felt her recovery was faster. “Every month I was getting better, gaining weight,” she says today, with the serenity of one who has been through the outdoors and back.

“At Socios En Salud we apply the same comprehensive support approach in clinical trials as we do in our community programs,” says Dr. Jimena Ruiz, coordinator of the Clinical Trials Unit.

Results that open a new horizon

In November 2024, the UNEC team traveled to Bali (Indonesia) for the World Conference of The Union on Lung Health, where preliminary results from the endTB-Q trial were presented. In July 2025, the journal The Lancet Respiratory Medicine published the full findings.

What was found? Well, that people who received a six- to nine-month experimental regimen of four key drugs - bedaquiline, delamanid, linezolid and clofazimine - achieved a cure rate of 87%, and up to 93% in those who started with limited disease.

Against the standard treatment of up to 18 months with injectables and severe adverse effects, this new regimen opens a shorter, safer and more tolerable path for those facing the most resistant form of tuberculosis.

Not all cases were straightforward: in people with very advanced TB, nine months was not enough to avoid relapse. But as Dr. Ruiz summarizes, “It is key to strongly accompany treatment, carefully manage side effects and sustain people’s trust.”

Dr. Ruiz summarizes, “It is key to strongly accompany treatment, carefully manage side effects and sustain people’s trust.

For Espinosa, that confidence allowed him to get through the endTB-Q trial and recover his life: the weight lost, the courage, the possibility of returning to work, no longer in masonry as before, but enough to support his family.

“There are humble people who do not have (money), people who want to get ahead, but with this disease they cannot. Now I know that the treatment is no longer a year, but up to six months. So it has come a long way,” he says.

In the living room of his house in Carabayllo, the saxophone remains in storage. Elvis Espinosa looks at it from time to time, like someone contemplating a promise. He doesn’t need to touch it to know that, after his illness, he has regained enough air to try again.