What are the health needs and challenges?

Leprosy is an infectious disease caused by Mycobacterium leprae bacteria, which multiply very slowly. Once infected, the average incubation period is five years, although it can take between 1 year and 20 years for symptoms to appear. Leprosy is not highly infectious and although its transmission is not fully understood, close and frequent contact with an infectious patient accelerates transmission. Leprosy mainly affects the skin and nerves. If untreated, there may be progressive and permanent damage to the skin, nerves, limbs and eyes. Disabilities are secondary complications that result from late diagnosis when the insensitivity (nerve damage) caused by leprosy is already present.

Multidrug therapy (MDT) is the treatment recommended by the World Health Organization (WHO). It consists of three drugs: dapsone, rifampicin and clofazimine – the latter two were developed in the research laboratories of Novartis. MDT has made it possible to treat patients, reduce the transmission of leprosy and prevent disabilities.

Since 1981, thanks to the free availability of MDT, the global disease burden has been reduced by 95%. Despite the decline, the case detection rate for leprosy has plateaued at about 200 000 cases over the past 15 years. But due to the COVID-19 pandemic, the number of new cases fell to 140 546 in 2021, leading to several thousands of missing cases. Maintaining awareness of the disease is particularly important in the aftermath of the pandemic, which has set us back on the journey to disease elimination.

Partnership activities and how they address needs and challenges

MDT donation: Since 2000, Novartis has been providing MDT free of charge to all leprosy patients through the WHO, helping to treat more than 7.5 million leprosy patients worldwide and reducing the global burden by 95%. In 2020, the company again renewed its pledge to extend its donation with the WHO through a new five-year agreement. The agreement also covers the continuing donation of triclabendazole for the treatment of fascioliasis. In 2022, at the Kigali Summit on Malaria and Neglected Tropical Diseases, Novartis announced a five-year (2021-2025) financial commitment of USD 250 million to advance R&D of new treatments to combat malaria and NTDs. In 2024, Novartis expanded its leprosy donation program with the WHO to include funding for single dose rifampicin (SDR) as post-exposure prophylaxis (PEP) to help interrupt transmission.

In recent years, fewer patients have been detected, and funding and political commitment as well as knowledge of the disease have also declined. The case detection rate for leprosy has plateaued at about 200 000 over the past 15 years, and the disease remains endemic in many countries in Asia, Africa and Latin America; even countries with low overall endemicity may have localized high-burden pockets. Further, newly diagnosed leprosy patients include children, indicating continued transmission of the disease, and high Grade 2 disability percentages, meaning the disease is not diagnosed at an early stage.

Post-exposure prophylaxis (PEP): Between 2013-2018, the Novartis Foundation worked with scientists, countries and patient groups to generate real world evidence on post-exposure prophylaxis with SDR – the largest ever research program on combining contact tracing with prophylactic treatment – an intervention recommended in the WHO’s Guidelines for the Diagnosis, Treatment and Prevention of Leprosy (2018).

In 2020, the results of the Leprosy Post-Exposure Prophylaxis (LPEP) program were published in The LANCET Global Health, indicating this approach could massively reduce the global burden of leprosy. Use of post-exposure prophylaxis has indeed shown to reduce the risk of leprosy in contacts of leprosy patients by up to 60%. The LPEP program traced 170 000 people who had been in contact with individuals newly diagnosed with leprosy and treated 150 000 of them with a SDR to prevent the disease.

If this approach is scaled up globally, near-elimination of leprosy could become a reality in a single generation.

AI4leprosy: An international team of scientists, led by Instituto Oswaldo Cruz (IOC/Fiocruz), Microsoft’s AI for Health team and the Novartis Foundation, has developed an AI algorithm that can help identify suspected leprosy lesions. The algorithm, AI4leprosy, takes into account skin lesion images in combination with patient symptoms. The results published in The LANCET Regional Health – Americas in 2022 show that the algorithm is over 90% accurate in detecting leprosy. Similarly, parallel efforts were taken up by data scientists from Novartis India, in collaboration with leprosy experts, to capture skin lesions from leprosy patients. An AI algorithm (Siamese Few Shot Learning) using images from approximately 150 leprosy patients was built, which could also differentiate leprosy skin lesions from non-leprosy skin conditions with an accuracy of above 70%. The results of this effort were published in the Indian Journal of Leprosy.

NTDeliver: Novartis is the sole supplier of MDT globally but supply alone is not enough. Converting treatments into cures requires an effective supply chain to ensure medicines reach patients on time. Currently, the supply chain for NTD medicines, including leprosy, is fragmented, involving many players, and requiring manual exchange of data files. To address these inefficiencies, Novartis subscribed to NTDeliver, a cloud-based supply chain optimization and visibility platform now used in more than 100 countries to digitally track donated medicines for NTDs from production to delivery through to central distribution points. This should substantially improve coordination across multiple stakeholders and ensure the timely and efficient supply of donated medicines for leprosy.