In 2022, a tiny study made oncologists gasp.
14 patients. 14 complete responses.
Every single tumour vanished.
No chemo. No radiation. No surgery.
It read like a typo.
It wasn't.
That drug was dostarlimab.
Four years later, it's back — with a much bigger trial and an even bigger claim.
Some rectal tumours have a glitch.
They can't repair damaged DNA.
So errors pile up. And up. And up.
Normally that's terrifying.
But it also makes them a sitting duck for immunotherapy — because a body riddled with mutations is easier for the immune system to spot and destroy.
This subtype hits 5-10% of the 730,000 rectal cancer cases diagnosed globally every year.
GSK's AZUR-1 trial — the follow-up act to that 2022 shocker — just hit its main goal.
A "clinically significant" share of patients showed zero detectable cancer for a year or more after treatment with Jemperli (dostarlimab).
No new safety red flags either.
Compare that to the current standard of care:
🔪 Surgery
☢️ Radiation
💉 Chemotherapy
🚽 Often a lifelong colostomy bag
🚫 Frequently, infertility
One path. Life-altering.
The other? A drug infusion.
Jemperli isn't new — it's already approved for a specific endometrial cancer subtype.
It quietly pulled in $1.1 billion in 2025 alone.
Now GSK is betting it becomes a cornerstone of its £40 billion ($53.5B) sales target by 2031.
The FDA already handed it Breakthrough Therapy and Fast Track status.
Translation: regulators are in a hurry too.
This isn't just one drug's data point.
It's a signal that immunotherapy could replace the operating table for an entire slice of cancer patients.
Not shrink the tumour.
Erase it.
GSK now takes this data to global regulators.
If it holds up at scale, thousands of patients a year could skip the knife entirely.
That's not incremental medicine.
That's a rewrite.
That's all for now!
