ASCO 2026: The Ovarian Cancer Trial Results Reshaping Treatment Standards

Once a year, the American Society of Clinical Oncology holds a meeting where the results of the world’s big cancer trials get presented for the first time. It is where treatment standards change — sometimes in the space of a single forty-minute session.

This year, ovarian cancer had a good meeting. Three trials in particular are worth understanding, and together they tell a story not just about new drugs but about how we decide what “working” means.

A word about the numbers first

Cancer trials report two main measures, and the difference between them matters enormously.

Progression-free survival (PFS) is how long someone lives before their cancer starts growing again. It’s the scan result. It answers: did the drug hold the line?

Overall survival (OS) is how long someone lives, full stop. It answers the only question anyone actually asked.

PFS is easier and faster to measure, so it’s often what a trial reports first. But treatments sometimes shrink tumors on a scan without adding a single day to a person’s life. When a trial improves overall survival, that is the real thing.

You’ll also see hazard ratios. A hazard ratio of 0.65 means the risk of the bad event — usually death — was 35% lower in the treatment group at any given moment. Below 1.0 is good. The further below, the better.

Keep those three in your pocket. They make the rest of this readable.

ROSELLA: teaching chemo to work again

The headline result of the meeting came from the ROSELLA trial, and it centers on a drug with an unusual mechanism: relacorilant.

Relacorilant isn’t chemotherapy and it isn’t immunotherapy. It blocks the glucocorticoid receptor — the docking station on your cells that responds to cortisol, the body’s stress hormone.

Here’s why that matters, and it’s genuinely surprising. Cortisol’s job in the body includes keeping cells alive under stress. It’s a survival signal: hold on, don’t die yet. Cancer cells hijack it. Chemotherapy comes in trying to trigger cell death, and the tumor is sitting there wrapped in a cortisol signal telling it to hang on. It’s a bulletproof vest, and the vest was already in the closet — cancer just learned to wear it.

Relacorilant takes the vest away. It doesn’t kill anything by itself. It makes the chemotherapy land.

The trial: 381 women with platinum-resistant ovarian cancer, randomly assigned to receive relacorilant (a 150 mg pill) plus nab-paclitaxel chemotherapy, or nab-paclitaxel alone.

The result: median overall survival of 16.0 months with the combination versus 11.9 months with chemotherapy alone — a hazard ratio of 0.65, meaning a 35% reduction in the risk of death, with a p-value of 0.0004. (A p-value that small means the odds of seeing a difference like this by pure chance are about four in ten thousand.)

The analysis was mature — 288 deaths, with a median follow-up of nearly 25 months — which matters, because early survival numbers can wobble and later ones usually don’t. And the benefit held across subgroups, including women who’d already had taxane chemotherapy before.

Two practical things make this result unusually useful. Side effects were broadly similar between the two groups: comparable rates of blood-count suppression and nerve damage, with slightly more neutropenia in the relacorilant group that researchers attributed to those women simply staying on treatment longer. And it requires no biomarker test — no PD-L1 status, no folate receptor level. Platinum-resistant disease is the only qualification.

Four extra months of median survival, from adding a pill. It’s the strongest result platinum-resistant ovarian cancer has seen in years.

CHIPRO: a real benefit, and an honest limit

The CHIPRO trial tested chiauranib, an oral multi-kinase inhibitor, added to weekly paclitaxel in women with platinum-resistant or platinum-refractory disease — meaning cancer that never responded to platinum in the first place, the hardest group of all to treat, and one usually left out of trials.

“Multi-kinase inhibitor” means the drug jams several of the cell’s signaling switches at once. Kinases are the relay stations of a cell — molecular switches that pass messages along, telling the cell to divide, to build a blood supply, to survive. Chiauranib blocks several at once: one (Aurora B) that cancer cells need to complete division, and others that tumors use to grow new blood vessels and to keep the surrounding immune environment friendly to them. It’s a scattergun rather than a sniper rifle.

The trial: 459 women, randomly assigned to weekly paclitaxel plus either chiauranib (228 women) or a placebo (231). It was double-blind — neither the women nor their doctors knew who was getting the real drug — which is the strongest design a trial can have, because it removes wishful thinking from both sides of the exam room. Participants received up to six cycles of the combination, and those whose cancer hadn’t progressed continued on chiauranib or placebo alone as maintenance.

The result: median progression-free survival of 4.57 months versus 2.69 months — nearly two extra months before the cancer grew again, a highly significant difference. More tumors responded, and responses lasted longer.

The limit: overall survival was not significantly different. The scans looked better. The lifespans, at least in this analysis, did not clearly change.

We include this because we think you deserve the unvarnished version. This is exactly the PFS-versus-OS gap we described up top, and it’s the reason researchers are careful. Grade 3 or higher side effects were also more frequent in the combination group, with more dose interruptions — though not more people quitting treatment altogether.

CHIPRO isn’t a failure. It’s real activity in the toughest population in the disease, with intriguing survival trends in specific subgroups that deserve a closer look. But it’s not yet the kind of result that changes what your oncologist offers you tomorrow.

CHRONO: sometimes the good news is “you can stop worrying”

The third trial answered a question that has quietly weighed on a lot of women and a lot of surgeons.

Many women with advanced ovarian cancer receive neoadjuvant chemotherapy — chemo before surgery — to shrink the tumor enough that the surgeon can remove all of it. The standard has been roughly three cycles, then surgery, then more chemo afterward.

The obvious question: if three cycles of chemo shrink the tumor, wouldn’t six cycles shrink it more, and make surgery easier and more complete?

CHRONO tested it directly. 209 women with stage IIIB–IVA high-grade ovarian cancer, median age 69, enrolled between 2018 and 2024, randomly assigned to either three cycles before surgery and five after, or six cycles before surgery and two after.

After a median follow-up of 40 months, disease-free survival was 20.2 months in the standard group versus 23.4 months in the delayed-surgery group — not a statistically significant difference. Complete surgical removal was achieved in 83.2% of the standard group and 90% of the delayed group. Major post-surgical complications occurred in 5% versus 11%. There were no surgical deaths in either arm.

The conclusion: waiting for six cycles doesn’t buy you anything meaningful. In women whose cancer is responding well to chemotherapy, there’s no reason to delay surgery hoping for a better result — and delaying may come with more complications.

Trials that show “the extra thing didn’t help” rarely make headlines, but this is genuinely useful. It means fewer women spending months in chemotherapy on the theory that more must be better, and more women getting to surgery on time. If you’re weighing this decision with your surgeon, CHRONO is a reasonable thing to bring up by name.

Also on the program

ASCO also saw the full presentation of KEYNOTE-B96 — the trial behind February’s FDA approval of pembrolizumab plus paclitaxel. Presented in full, it confirmed a significant overall survival benefit both in women whose tumors are PD-L1 positive and in the trial population as a whole — described by commentators as among the longest survival results reported in any trial in this setting.

What it adds up to

A doctor writing notes at a desk — Trial results only matter once they reach a consulting room. These are worth raising by name at your next appointment.

For the first time in a long while, women with platinum-resistant ovarian cancer have more than one reasonable option, and choosing between them is starting to depend on the specific tumor rather than on what’s left on the shelf.

Broadly, the emerging approach looks like this: test the tumor for folate receptor alpha, and if it’s high, an antibody-drug conjugate aimed at that target may spare a woman more taxane chemotherapy and the cumulative nerve damage that comes with it. Below that threshold, relacorilant plus nab-paclitaxel now works regardless of prior taxane exposure. Where PD-L1 status and the biology support it, pembrolizumab plus weekly paclitaxel is an increasingly compelling choice given its survival data.

That’s not a decision tree you should try to apply to yourself — your oncologist weighs a dozen things this article can’t see. But it is a decision tree, and three years ago there barely was one.

Questions worth bringing to your next appointment: Has my tumor been tested for folate receptor alpha and PD-L1? Is relacorilant plus nab-paclitaxel an option for me? If I’m facing neoadjuvant chemotherapy, what’s our plan for surgical timing?

You are allowed to ask about trials by name. Good oncologists like it when patients do.

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