Asco 2019 event analyser – low-key meeting belies some huge stock moves

For years Asco has been a highlight in the biopharma calendar. This status remains unshaken after this year's meeting, as illustrated by the number of companies that saw big share price gains – and falls – in the wake of their Asco presentations.

However, in terms of hard data this year’s conference was one of the most lacklustre in recent memory, and remarkably one of its biggest beneficiaries, Mirati Therapeutics, did not even present at the meeting. Meanwhile, Sierra and Aduro were the most heavily punished for disappointing clinical trial results.

To measure the effect of Asco-related share movement Vantage analysed changes from the market’s close on May 15, just before the meeting’s abstracts were released, through June 4, the final day of the conference. Companies are ranked by percentage change in share price.

TIL next time

Mirati was not quite the champion of Asco; that honour went to Iovance Biotherapeutics, which added $787m to its market cap on data with its project comprising tumour infiltrating lymphocytes, or TILs, in melanoma and cervical cancer.

However, there are doubts about the commercial prospects of TILs, even if they work. In particular, there are questions about whether such therapies, which are based on a patient’s own unmodified cells, can be patented.

Mirati climbed 54% on the back of this year’s Asco KRAS buzz. Positive but early results with Amgen’s AMG 510 raised hopes that Mirati’s similarly acting candidate, MRTX849, could also be a success. 

Still, Amgen has set the bar high with a 50% response rate. If MRTX849 falls short of this in its first clinical readout later this year, Mirati, which now looks overvalued, looks set to tumble.

Another beneficiary of the AMG 510 data was Array Biopharma, which originated MRTX849 and will receive royalties from Mirati should the project reach the market. Meanwhile, Amgen itself saw its valuation grow $3bn over the Asco period, showing just how important the KRAS inhibitor is to the big biotech.

As for the other big winners, Oncopeptides’ rise was mainly down to news that it would apply for US accelerated approval of its lead candidate, melflufen. The company also presented data at Asco from the phase I/II O-12-M1 study in multiple myeloma; the abstract looked similar to the one submitted for the upcoming European Hematology Association conference.

And the newly public Turning Point Therapeutics benefited from encouraging responses to its targeted therapy repotrectinib in Ros1-positive non-small cell lung cancer, which had analysts suggesting that the compound could emerge as the best in its class. Even if this is the case, repotrectinib would have a tough time competing against bigger players in this space. 

Sting in the tail

The biggest loser of this year’s Asco, Sierra Oncology, saw its share price slip below a dollar on Monday after reporting data with its Chk1 inhibitor SRA737 in anogenital cancer. However, the company got a boost today after its lead candidate, momelotinib, was granted fast-track designation by the US FDA.

Meanwhile, Aduro also crashed on Monday on detailed results with its Novartis-partnered Sting agonist, ADU-S100. A phase Ib study of the project in combination with Novartis’s PD-1 blocker spartalizumab, in solid tumours and lymphoma, found responses in just five of 57 evaluable subjects.

Aduro has dropped development in melanoma. It might be able to salvage something in triple-negative breast cancer, where data looked more promising, albeit in a small number of patients so far.

And an early look at Moderna’s personalised cancer vaccine mRNA-4157 failed to enthuse investors. A phase I trial of the vaccine, given alone or in combination with Merck & Co’s Keytruda, showed hints of an immune response, so perhaps Moderna bulls need to see data from an upcoming randomised phase II trial to be convinced.

Another Asco faller was Macrogenics, which sank 17% yesterday as more comprehensive results from the Sophia study of margetuximab fuelled doubts about whether this project would show a survival benefit. Even if the drug is approved its chances of commercial success look slim.

Nektar’s overall share price move also belies a tumultuous couple of weeks. The company dipped on the initial Asco abstract drop, then rose strongly after Saturday’s data presentation exceeded expectations, before falling away again, perhaps as investors took their chance to sell shares.

Investors might need to see more action at next year's Asco if the meeting is to retain its unmissable status.