Targeted Therapy: What It Is, How It Works, and What You Need to Know

When you hear targeted therapy, a type of cancer treatment that attacks specific molecules driving tumor growth. Also known as precision medicine, it doesn’t just blast cells—it picks out the ones that matter. Unlike chemotherapy, which hits fast-growing cells whether they’re cancerous or not, targeted therapy zeroes in on the exact genetic or protein changes that make cancer cells different from healthy ones. This means fewer side effects for many patients and more control over how the disease behaves.

Targeted therapy works because cancer isn’t one disease—it’s hundreds. Each tumor has its own unique set of mutations. Some have HER2 proteins, others rely on EGFR, BRAF, or ALK changes. Drugs like trastuzumab for HER2-positive breast cancer or vemurafenib for BRAF-mutant melanoma were designed to block those exact signals. This is why your doctor might test your tumor tissue before starting treatment. It’s not a guess—it’s a map. And if the cancer changes over time, new mutations can appear, leading to drug resistance, when targeted drugs stop working because the cancer evolves. That’s why many patients switch therapies or combine them with other treatments.

Targeted therapy isn’t just for advanced cancer. It’s now used in early stages to reduce recurrence after surgery. It’s also being tested in non-cancer conditions like autoimmune diseases and rare genetic disorders. But it’s not magic. Not everyone responds, and some tumors don’t have clear targets yet. Still, the field is growing fast. New drugs are approved every year, and researchers are learning how to predict who will benefit most—using blood tests, AI, and better imaging.

What you’ll find in the posts below is a practical look at how targeted therapy connects to real-world treatment choices. You’ll see how it relates to medications like atazanavir and lamotrigine, not because they’re cancer drugs, but because they show how drug interactions, side effects, and patient-specific factors shape outcomes. You’ll read about how genetics influence treatment success, how lifestyle choices like smoking can interfere, and how alternatives are compared to find the best fit. This isn’t theory. It’s what people are living with—every day.