Targeted therapies do not attack every cancer in the same way. They are designed for tumours carrying particular molecular changes, so biomarker testing is central to treatment selection.
Targeted therapy ka basic idea
Cancer is not one single disease. Tumour cells can carry mutations or abnormal proteins that help them grow. A targeted drug is designed to block a selected molecular driver, rather than simply treating every rapidly dividing cell in the same way. Isliye do patients ko same organ ka cancer hone ke baad bhi different medicines mil sakti hain: their biopsy and biomarker reports may show different targets.
Vorasidenib: targeting mutant IDH enzymes
Vorasidenib inhibits mutant IDH1 and IDH2 enzymes. On August 6, 2024, the US FDA approved it for patients aged 12 years and older with certain Grade 2 astrocytomas or oligodendrogliomas carrying a susceptible IDH1 or IDH2 mutation after surgery. The phase 3 INDIGO trial studied 331 patients and reported longer progression-free survival and delayed time to the next intervention compared with placebo. This does not mean it treats every brain tumour; the mutation, tumour type, grade, treatment history, and clinician's assessment all matter.
Lorlatinib: blocking ALK-driven lung cancer
Lorlatinib is a third-generation ALK tyrosine-kinase inhibitor used for ALK-positive metastatic non-small-cell lung cancer. ALK is a growth-signalling protein; in some tumours, an abnormal ALK fusion keeps that signal switched on. Lorlatinib is designed to enter the brain and inhibit ALK, which matters because this cancer can spread to the central nervous system. The five-year CROWN study update reported strong progression-free and intracranial outcomes compared with crizotinib in previously untreated advanced ALK-positive disease.
Why biomarker testing comes before the drug
A medicine aimed at mutant IDH will not automatically help an ALK-driven tumour, and an ALK inhibitor is not a universal lung-cancer pill. Doctors use pathology, molecular tests, imaging, disease stage, previous treatment, side-effect risks, and patient health to choose therapy. Precision medicine therefore follows a chain: identify the tumour, test the molecular driver, match an evidence-based medicine, and monitor response and safety.
Important safety note
This article explains biology and published evidence; it is not medical advice. Both medicines can cause significant adverse effects and require specialist supervision and laboratory or clinical monitoring. Patients should never start, stop, or change cancer treatment from a Short, article, or social-media post. Treatment decisions belong with the oncology team that has the complete medical record.
Concept Map
Fast facts
| Vorasidenib target | Mutant IDH1 and IDH2 enzymes in eligible Grade 2 glioma. |
| Lorlatinib target | ALK signalling in ALK-positive metastatic non-small-cell lung cancer. |
| Selection tool | Tumour pathology and biomarker testing. |
| Core distinction | Targeted does not mean side-effect free or suitable for every cancer. |
| Evidence | FDA vorasidenib approval, INDIGO trial, and CROWN five-year outcomes |
Did you know?
The same cancer label can contain several molecular subtypes. A biomarker can sometimes tell doctors more about drug choice than the organ name alone.
Watch the short here: open the YouTube explanation.
Key takeaway
Targeted therapy means target first, medicine second. Vorasidenib and lorlatinib illustrate how mutation testing can connect a particular tumour pathway with a particular drug.
