ASCO 2017: 4 ways treatment could change following world’s largest cancer conference

Close to 40,000 delegates descended on Chicago at the start of the month for the world’s largest gathering of cancer experts, the American Society of Clinical Oncology (ASCO) Annual Meeting.

Scientists, doctors and patients were there to hear the latest clinical trial results and catch a glimpse of exciting new developments. And with thousands of pieces of research on show, there was a lot to take in.

Here are 4 areas we think are worth watching out for.

1. Prostate cancer progress

Headline grabbing results from 2 large clinical trials showed that offering the prostate cancer drug abiraterone (Zytiga) earlier can improve survival for some men.

The Cancer Research UK-funded STAMPEDE trial included men whose prostate cancer had spread, or had a high risk of doing so, and were about to start standard hormone therapy. The results showed that adding abiraterone and the steroid prednisolone to standard hormone therapy extended the lives of these men.

Professor Nick James, who led the study, said that seeing the results come together was a “once in a career feeling”. And he believes that offering abiraterone up front for these men could become the new standard of care.

The take home message was the same for a second trial called LATITUDE, which also put earlier treatment with abiraterone through its paces.

Combining abiraterone and standard hormone therapy lowered the risk of death in men whose prostate cancer had already spread at the time of diagnosis. And the combined treatment more than doubled the time before patients’ disease worsened.

There was plenty of excitement around these results, signalling promise for offering abiraterone earlier in these men. It’ll now come down to careful scrutiny over the results as they mature, alongside the cost of the drug, before a decision is made around making it available for those who would benefit.

2. Location, location, location… or maybe not

Following last year’s conference we wrote about how, in some cases, decisions around treatment are beginning to move away from being based on where a tumour is growing in the body.

This year there were updates on how this approach is starting to show promise.

Just before the meeting opened the immunotherapy drug pembrolizumab (Keytruda) was approved by the FDA in the US to treat any tumour that carries a characteristic genetic fingerprint.

And new data presented at the conference showed why.

In a small study of 86 patients with 12 different types of cancer, over half of tumours carrying a distinctive type of heavy genetic damage responded to the immunotherapy drug. Those responses were independent of the tissue or organ in which the tumour originated, showing that characteristics of tumours can be shared and may help predict which drugs will work or not.

According to our chief clinician, Professor Peter Johnson, the FDA’s move to approve pembrolizumab in this way “marks the start of a new era in how we think about cancer therapy”. And he anticipates more decisions like this in the future.

An early sign that this might be the case came from a small clinical trial testing a new drug that has been developed without a particular tumour type in mind.

The drug, called larotrectinib, targets rare faults in a molecule called tropomyosin receptor kinase (TRK). And results presented at the conference from ongoing phase 1 and 2 trials showed that 38 of 50 patients treated with the drug had seen their tumours shrink to some degree.

But the big difference between these trials and others on show is that they include patients with 17 different types of advanced cancer, and both adults and children.

These are preliminary data, so there’s a long way to go before it will become clear if the approach will benefit these patients. But there was excitement at the conference for what the possible approval of the drug in the US might mean for the future of precision medicine.

“If approved, larotrectinib could become the first therapy of any kind to be developed and approved simultaneously in adults and children,” said Dr David Hyman, chief of early drug development at Memorial Sloan Kettering Cancer Center in New York, who led the study.

“These findings embody the original promise of precision oncology: treating a patient based on the type of mutation, regardless of where the cancer originated,” he added.

3. Targeted treatment trials

The results of several large clinical trials of new targeted drugs were highly anticipated by doctors in the build up to the conference. And they didn’t disappoint.

As we reported from the conference, the olympiAD trial showed that an ovarian cancer drug can hold some advanced breast cancers at bay longer than standard chemotherapy.

Tumours shrank in about 60% of women who received the targeted drug, called olaparib (Lynparza), compared with 29% of those who received chemotherapy. This improvement also came with fewer side effects.

In two advanced lung cancer trials, which we covered, new drugs targeting familiar faulty molecules showed promise.

The drug alectinib (Alecensa), which targets a faulty version of the ALK gene, halted the growth of non-small cell lung cancers for 15 months longer than the standard ALK-targeting treatment, a drug called crizotinib (Xalkori).

And in a separate trial the drug dacomitinib delayed the growth of lung tumours carrying a faulty EGFR gene for longer than the drug gefitinib (Iressa), one of the standard targeted medicines for lung cancers with faulty EGFR.

Experts said the results could change the standard of care for people with these hard to treat lung cancers. So watch this space.

4. Are two drugs better than one?

If you’ve an eye on the latest developments in cancer it’s hard to miss immunotherapy. A growing collection of immune-boosting treatments have produced remarkable results in some advanced cancers. But these responses remain the exception, rather than the norm.

To try and tackle this, and increase the number of people who may benefit, scientists and doctors are starting to combine treatments in clinical trials. Some are doubling-up on the immunotherapy hit, while others are testing immunotherapy alongside targeted drugs, chemotherapy or radiotherapy.

It’s still early days for most of the trials presented at the conference that are using this approach, but the sheer number underway (several hundred according to some estimates) shows this is an area to watch (especially as combinations could come with the challenge of worse side effects).

We did pick up on one promising example of where this might work: melanoma that has spread to the brain.

Two trials found that a combination of immunotherapy drugs was safe to give to these patients, something that wasn’t known before. And as we reported, half of melanomas that had spread to the brain responded to, or were kept stable by, the combined effects of the drugs ipilimumab (Yervoy) and nivolumab (Opdivo).

The number of patients in these trials was small, but the results point to a potential new treatment option if confirmed in future studies.

Who, what, where and when

These 4 areas capture where we’re at with research right now. Scientists and doctors are on the hunt for more details about each patient’s cancer, studying why treatments work for some but not others.

In some cases that means testing when is best to offer these drugs, as shown by the prostate cancer trial results that suggest a strong combination attack works well up front.

The approach to treatment is also becoming more precise. And the way we define tumours based on where they are in the body is beginning to shift.

Each of these areas is focused on finding treatments that are most likely to work for each patient. And after 5 days of talks, with thousands of pieces of research on show, the challenge now is keeping up.

Nick