DRUG-RESISTANT TB

2. About drugresistant TB

• As of 2017, India accounted for around one-fourth of the world's burden of multidrug-resistant (MDR) TB and of extensively drug-resistant (XDR) TB and extensively drug-resistant (XDR) TB.
• MDR TB resists treatment by at least two frontline drugs in TB treatment, isoniazid and rifampicin.
• XDR TB resists these two drugs, fluoroquinolones, and any second-line injectable drug.
  XDR TB is rarer than MDR TB there were 1, 24, 000 cases of the latter in India (2021) versus 2, 650 cases of the former (2017).
• TB incidence in India has been on the decline, but MDR TB and XDR TB endanger initiatives to locally eradicate the disease.
• In the first two years of the pandemic, there were reports that TB treatment was hit by disrupted supply chains, availability of healthcare workers for non-pandemic work, and access to drug distribution centres.
• A peer-reviewed 2020 study found that the incidence of MDR TB was "strongly correlated with treatment failure and spread through contact and not to treatment compliance".

3. Treatment for drug-resistant TB

• TB is an infection of the bacterium Mycobacterium tuberculosis in the lungs, but often in other organs as well.
• It can be treated by strictly adhering to the doses and frequencies of drugs prescribed by a physician.
• Deviations from this schedule can lead the bacteria to become drug-resistant.
• Yet they happen because the drugs often have side effects that diminish the quality of life and or because patients haven't been afforded access to the requisite drugs on time.
• Drugresistant TB is harder to treat. One important option for those diagnosed with pulmonary MDR TB is bedaquiline.
• In 2018, the World Health Organisation replaced two injectable drugs for MDR TB with an oral regimen that included bedaquiline.
• At this time, bedaquiline had not completed phase III Trials.
• The recommendation was based on smaller studies, outcomes in TB elimination programmes worldwide, the difficulty of treating MDR TB and close monitoring of patients receiving the drug.

4. Effectiveness of Bedaquiline

• Typically, bedaquiline needs to be taken for six months: at a higher dose in the first two weeks followed by a lower dosage for 22 weeks.
• This period is shorter than other treatment routines for pulmonary MDR TB, which can last 924 months.
• One phase II Clinical trial observed that culture conversion (turning a patient's sputum culture from positive to negative) "at 24 weeks was durable and associated with a high likelihood of response at 120 weeks", due to bedaquiline.
• Unlike Second-line treatment options that are injected and can have severe side effects, like hearing loss, bedaquiline is available as tablets and is less harmful, although it has potential side effects of its own.
• Studies until 2018 found that it could be toxic to the heart and the liver. This is part of why it is recommended only as a treatment of last resort.
• India's Health Ministry has guidelines for bedaquiline use as part of the Programmatic Management of MDR TB under the National TB Elimination Programme.
• The WHO's decision revitalised a debate about the ethics of making a much-needed but insufficiently tested drug available quickly versus lowering the safety threshold for pharmaceutical companies producing drugs for desperate patients.

5. Reasons for the rejection of the Patent application

• Both groups argued that J&J's method to produce a "Solid pharmaceutical composition" of bedaquiline is "obvious, known in the art" and doesn't require an "inventive step".
• According to the Indian Patent Act 1970 Section 2 (1) (ja), an "inventive step" is an invention that is "not obvious to a person skilled in the art".
• The latter also contended that the current application drew significantly from a previous patent, WO 2004/011436, which discussed a similar compound on which bedaquiline is based and whose priority date (2002) well preceded the new application.
• The Patent Office rejected the application on these and other grounds, including Sections 3d and 3e of the Act.
• These pertain to the "mere discovery of a new form of a known substance which does not result in the enhancement of the known efficacy of that substance" and "a substance obtained by a mere admixture resulting only in the aggregation of the properties of the components thereof", respectively, which are not patentable.

6. Significance of the rejection 

• India has the largest population of people living with drug-resistant TB.
• J&J's patent on bedaquiline meant the drug cost $400 (revised to $340 in 2020) per person, plus the cost of other drugs.
• The rejection is expected to lower the cost of bedaquiline by up to 80 per cent.
• So far, the Indian government has directly procured and distributed the drug through Statelevel TB programmes.
• After July 2023, manufacturers of generic drugs such as Lupin will be able to produce generic versions of bedaquiline.
• The argument based on WO 2004/011436 is also relevant to "evergreening a strategy where a patent owner continuously extends their rights and or applies multiple patents for the same entity. Indian law disallows this.

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