What happened

bluebird bio (BLUE -1.07%) closed up 11.2% on Wednesday, continuing its three-day run following the presentation at the American Society of Clinical Oncology (ASCO) meeting on Monday.

Positive comments from J.P. Morgan biotech analyst Cory Kasimoc could be helping extend Bluebird's run. All told, the biotech is up 29.7% from Friday's close.

So what

The ASCO presentation was on Bluebird's CAR-T treatment, bb2121, which is partnered with Celgene (CELG). In a phase 1 trial, 100% of the multiple myeloma patients who received the three highest doses responded to the bb2121 treatment, which consists of taking immune cells out of the patient, training them to attack cancerous cells expressing a protein called BCMA, and then putting the cells back into the patient where they can attack.

It was a rather small trial with just 15 patients getting the highest three doses, but the results are quite impressive considering that all of the patients had failed a median of seven prior therapies.

Doctor with patient in hospital bed

Image source: Getty Images.

Now what

Bluebird and Celgene plan to enroll additional patients in the trial to determine the optimal dose of bb2121 before moving on to the next clinical trial, which regulators will hopefully deem sufficient for approval.

The duo would be well advised to move as quickly as possible into a pivotal trial because they appear to have competition from a Chinese company, Nanjing Legend Biotech, which is also developing a CAR-T treatment targeting BCMA. At an ASCO presentation Nanjing showed its drug can also produced a 100% objective response rate. The fraction of patients achieving a complete response was higher in Nanjing's trial, but it's hard to compare across trials as it appears Nanjing enrolled patients that weren't as sick as the patients in Bluebird and Celgene's trial.

Nevertheless, investors should keep an eye on Bluebird and Celgene's development pace from here.