GENEVA, Oct 28: The World Health Organization (WHO) has released new guidance outlining the desired characteristics of long-acting injectable treatments for tuberculosis (TB), seeking to accelerate the development of medicines that could make treatment more convenient for patients and improve disease control.
The guidance, announced on October 28, establishes target product profiles for long-acting injectable formulations intended for TB treatment. These profiles describe the preferred characteristics that future medicines should have, including their intended use, safety, effectiveness and practical suitability for patients and healthcare systems.
The initiative comes as countries continue efforts to reduce TB-related illness and deaths while addressing challenges associated with lengthy treatment courses, medication adherence and drug-resistant infections.
TB remains one of the world’s leading infectious disease threats. Although effective treatments are available, patients often need to take multiple medicines over several months. The length and complexity of treatment can make it difficult for some people to complete their prescribed regimens, increasing the risk of treatment failure, relapse and the development of drug resistance.
The WHO’s latest guidance aims to encourage researchers and pharmaceutical developers to design long-acting injectable medicines that could simplify treatment delivery and address some of these challenges.
Long-acting medicines could reduce treatment burden
Conventional TB treatment generally requires patients to take oral medicines regularly over an extended period. Depending on the form of the disease and the medicines prescribed, treatment can involve several drugs and frequent monitoring by healthcare professionals.
For patients who live far from health facilities, travel costs, time away from work and difficulties obtaining medicines can create additional barriers to completing treatment.
Long-acting injectable formulations are designed to release medicines gradually, potentially maintaining therapeutic drug levels for longer periods and reducing how frequently doses must be administered.
If effective and approved for appropriate TB regimens, such treatments could reduce the need for frequent medication-taking and make it easier for healthcare providers to supervise treatment.
However, the potential benefits depend on the medicines’ pharmacological properties, safety, effectiveness and suitability for different patient groups. Researchers must establish how long the injections remain effective, whether they can be combined safely with other TB drugs and how adverse effects should be monitored.
The WHO’s target product profiles are intended to guide research towards formulations that respond to these clinical and practical requirements.
Tuberculosis continues to pose a global health challenge
TB is caused by bacteria that most commonly affect the lungs, although the disease can also involve other parts of the body.
It spreads through the air when a person with infectious pulmonary TB releases bacteria by coughing, speaking or singing. Prolonged close exposure can increase the risk of transmission, particularly in crowded or poorly ventilated environments.
Common symptoms include a persistent cough, fever, night sweats, fatigue and unexplained weight loss. Not everyone with TB develops symptoms immediately, and some people have a latent infection that does not cause illness or spread to others.
Early diagnosis and appropriate treatment are essential to prevent complications and interrupt transmission. Diagnostic testing helps determine whether a person has TB and, where necessary, whether the bacteria are resistant to particular medicines.
Although TB is preventable and treatable, its burden remains high in countries where poverty, malnutrition, overcrowded housing and limited access to healthcare make diagnosis and treatment more difficult.
People living with HIV and those with certain other health conditions can face a greater risk of developing active disease. Access to timely screening and appropriate treatment is therefore important for reducing illness and preventing deaths.
Drug resistance complicates treatment
Drug-resistant TB presents a particularly serious challenge for public health authorities.
Some forms of the disease do not respond to the medicines commonly used for standard treatment. Patients may need alternative combinations of drugs, additional monitoring and more specialised care.
Treatment for drug-resistant TB can be complicated by adverse effects, medication costs and difficulties maintaining adherence over time.
Long-acting injectable medicines could offer potential advantages if researchers establish that they are effective against relevant strains and can be safely incorporated into suitable treatment regimens. However, a long-acting formulation would not automatically overcome bacterial resistance.
The effectiveness of any future medicine would depend on the drug’s activity against the infection, its interaction with other treatments and the ability to maintain effective concentrations without causing unacceptable side effects.
Researchers must also consider what happens if a medicine remains in the body for an extended period after treatment is stopped or if a patient develops an adverse reaction. These issues are important because a long-acting formulation may not be removed from the body as quickly as a short-acting medicine.
The WHO’s guidance can help developers identify these scientific and clinical requirements at an early stage.
Research guidance seeks to encourage innovation
Target product profiles are tools used by public health organisations to communicate the characteristics needed in future medical products.
They help researchers, manufacturers, funders and regulators understand which clinical needs should guide product development.
For long-acting TB injections, important considerations include the duration of action, safety, effectiveness, dosing requirements, compatibility with other medicines and ease of administration.
Affordability and accessibility are also critical. A treatment that works well in clinical trials may have limited public health impact if it is too expensive or requires specialised facilities that are unavailable in high-burden countries.
The WHO’s guidance is intended to encourage the development of products that can meet both medical and practical needs.
Such planning can help direct investment towards formulations that have the potential to improve treatment outcomes while remaining feasible for healthcare systems with limited resources.
However, target product profiles are not the same as clinical trial results or regulatory approval. They establish development goals rather than confirm that a particular medicine is safe, effective or ready for use.
Candidate products will still need appropriate laboratory research, clinical trials and regulatory assessment before they can be recommended for routine treatment.
India has a major stake in improved TB treatment
India is central to global efforts to control tuberculosis because of the substantial burden of the disease in the country.
The Indian government has pursued measures to expand testing, improve access to treatment, strengthen nutritional support and identify cases earlier through its national TB elimination programme.
Challenges include delayed diagnosis, stigma, treatment interruptions and the need to reach vulnerable populations in remote and underserved areas.
Patients may also face difficulties attending repeated appointments because of travel expenses, employment commitments and family responsibilities.
If safe and effective long-acting injectable TB medicines become available in the future, they could potentially support treatment delivery for selected patients, depending on the approved indications and recommendations.
Such formulations could be particularly useful where reducing the frequency of medicine administration would improve continuity of care. Nevertheless, injections would still require trained healthcare personnel, appropriate monitoring and dependable supply systems.
India would also need to assess affordability, manufacturing capacity and the feasibility of introducing new formulations within existing TB services.
The availability of a new delivery method alone would not eliminate the need for early diagnosis, contact investigation, preventive treatment where appropriate and continued patient support.
Access and affordability remain essential
Public health experts have long emphasised that new TB medicines must reach the people who need them most.
Developing a treatment is only one stage of the process. Countries must also ensure reliable procurement, distribution, trained staff and systems for monitoring treatment outcomes.
For long-acting injections, delivery costs could include the medicine itself, administration, follow-up appointments and monitoring for adverse reactions. These factors will influence whether the approach is practical in different healthcare settings.
Patients living in remote communities may benefit from less frequent dosing, but only if the treatment is accessible and the necessary medical services are available when required.
Healthcare authorities will also need to determine which patients are suitable candidates and whether particular formulations can be used alongside existing medicines.
Equitable access will depend on cooperation among governments, researchers, manufacturers, funding agencies and international health organisations.
New formulations must undergo rigorous testing
The WHO’s guidance represents a step towards encouraging innovation, but it does not mean that long-acting injectable TB treatments are already available for general use.
Potential medicines must demonstrate that they achieve effective drug concentrations, provide meaningful clinical benefits and have acceptable safety profiles.
Clinical studies will need to establish appropriate dosing schedules and evaluate how new formulations compare with established treatments. Researchers must also examine whether the injections can be used in combination regimens without compromising effectiveness.
Long-term monitoring will be important for identifying adverse effects, treatment failures and the possible emergence of resistance.
Patients should continue to follow treatment prescribed by qualified healthcare professionals and should not change or discontinue existing TB medicines because of reports about experimental formulations.
Global cooperation will shape future progress
The development of long-acting TB treatments will require coordinated research and sustained investment.
Pharmaceutical companies, academic institutions, public health agencies and international funders can work together to identify promising compounds, conduct clinical trials and address regulatory requirements.
The WHO’s target product profiles provide a framework for aligning these efforts with public health priorities.
The guidance also highlights the importance of designing medical innovations around the needs of patients and healthcare systems, rather than focusing solely on the properties of a drug.
If successful products emerge, they could become part of a broader strategy to improve treatment adherence, strengthen disease control and reduce the burden of tuberculosis.
For now, established diagnostic services, effective medicines, patient support and infection-prevention measures remain essential components of TB control.
The WHO’s latest initiative marks an effort to encourage the next generation of treatment options, with the ultimate objective of making tuberculosis care more effective, accessible and manageable for patients worldwide.