Bengaluru: A new breakthrough has been announced that would enable doctors to quickly and accurately prescribe the most effective drug to a tuberculosis patient without a trial and error process, followed currently that takes a month.
SPIT SEQ, developed by MedGenome Labs, is the first Whole Genome Sequencing based test that can provide a detailed analysis of every single mutation present in any tuberculosis bacteria causing drug resistance − directly from the sputum.
India has the largest number of multi drug resistant (MDR-TB) TB cases. SPIT SEQ can be a boon for TB patients, clinicians and healthcare agencies to achieve India’s Sustainable Development Goal (SDG) of eliminating TB by 2025.
SPIT SEQ is based on whole genome sequencing of mycobacterium tuberculosis (MTB), the TB causing bacteria, to assess the mutations in bacteria’s genome and allows a clinician to determine which drugs will work for a patient.
The test has been validated with over 100 samples where it recorded with 100% sensitivity and 98.04% specificity when compared with Line Probe Assay (LPA). Fifty out of those samples were in association with PD Hinduja Hospital and Medical Research Centre, Mumbai. A manuscript is under review for publication.
Typically, the process of analysing the drug resistance is very long which delays treatment for MDR-TB patient. Here as well, the current expertise allows testing resistance only on 4 drugs hence the patient had to wait until testing on all possible drug concluded. In such a situation, where it took a long turn-around diagnosis time, repeated testing led to multiple changes in the course of treatment along the way.
“Direct Whole Genome Sequencing reveals information on drug resistance mutations for all anti TB drugs in a matter of 10 days. Soon, this technology will help in optimizing the precise management of an MDR-TB patient,” said Dr Camilla Rodrigues, Consultant Microbiologist & Chairperson – Infection Control Committee, P D Hinduja Hospital and Medical Research Centre, Mumbai.
According to a WHO report, there were 2.7 million TB cases (incidence + relapse) in 2017 and India accounted for 27% of global TB deaths. Second most appalling insight is that globally, 3.5% of the new TB cases and 18% of previously treated patients suffered from relapse due to the immunity developed by tuberculosis bacteria. The conventional tests available in the country equip doctors to identify resistance in a limited fashion.
MTB (Mycobacterium tuberculosis) grows slowly and takes 6-8 weeks for culture growth, thereby delaying not only TB diagnosis but also the drug resistance testing.
SPIT SEQ is a culture-free WGS (whole genome sequencing) method for identification of MTB and prediction of drug resistance with a turnaround time of 10 working days.
Another strength of WGS over rapid molecular tests (LPA) is in the resolution of non-interpretable (NI) results that occur when a locus of interest has neither the wild type nor the specific mutation of interest present. A total of 12 such mutations were detected by the SPIT SEQ WGS test, which was missed by LPA.
“SPIT SEQ is a massive breakthrough that can help millions. This particular test does not only bring accurate results but also saves a lot of time where TB treatment is concerned. In lines with India’s objective to counter TB effectively and quickly, we aim to benefit the last person living with TB today,” said Dr V L Ramprasad, COO, MedGenome Labs.
MedGenome Labs is a leader in clinical data driven genetic diagnostics and drug discovery research in India.