One arm grabs the cancer cell. The other grabs a T-cell. The bispecific forces them together.
CAR-T cell therapy works but takes weeks to manufacture and costs $400K+ per patient. T-cell engager bispecific antibodies do the same job as an injectable drug - no cell extraction, no manufacturing delay. Ten are now FDA-approved across myeloma, lymphoma, leukemia, and solid tumors, competing directly with CAR-T in the same diseases.
Pfizer, Amgen, Lilly, Merck, and Astellas all failed at IGF-1R in cancer. Then a shelved Roche antibody became the only effective treatment for thyroid eye disease. Same receptor, completely different biology.
Five major pharmas spent two decades chasing IGF-1R as a cancer target. Every Phase 3 trial failed. The only IGF-1R drug ever approved is for thyroid eye disease — Tepezza, which generated $1.9 billion in 2024 and 8x exceeded its acquirer's peak forecast. Eleven more IGF-1R-for-TED programs are now in clinical trials, including the literal cancer-graveyard compound being resurrected by Sling Therapeutics. Targets don't travel. Disease context decides.
It took 40 years to drug KRAS. The real competition started the day it worked.
KRAS mutations drive roughly 30% of all cancers. For four decades, no one could drug it. In 2021, sotorasib cracked the target. Now three approaches - next-gen G12C, G12D inhibitors, and pan-KRAS degraders - are racing to turn a proven mechanism into a blockbuster.
A biosimilar approved in 2016. Still shelved in 2026.
Sandoz's Erelzi received FDA approval in August 2016. Nearly a decade later, it still hasn't launched in the US - while the same drug has been selling in Europe since 2017. The patent cliff is set for 2029. An antitrust challenge was dismissed in February 2026 and is now on appeal.
Amgen got FDA approval for Amjevita in September 2016. It shipped its first US vial in January 2023. Six and a half years between approval and market entry - and nine more Humira biosimilars followed the same pattern. The gap between "approved" and "on sale" isn't a quirk of Humira. It's how biologics competition works.
How a genetic discovery in 2003 launched a $5 billion market.
In 2006, researchers found people born with broken copies of PCSK9 had very low cholesterol and almost no heart attacks. They were healthy. That was the signal. Four drugs across three different modalities now target the same gene - a combined market exceeding $5 billion in 2025.