The current CAR-T party of two might have a couple of new companions on the way. And those new entrants could bring some excitement to the party.

Only two chimeric antigen T-cell receptor (CAR-T) therapies are currently approved by the FDA -- Novartis' Kymriah and Gilead Sciences' Yescarta. Celgene (NASDAQ:CELG) and partner bluebird bio (NASDAQ:BLUE) announced good news for another experimental CAR-T therapy, bb2121, at the American Society of Clinical Oncology (ASCO) annual conference on Friday. Celgene followed up by presenting positive results for CAR-T therapy JCAR017 at the ASCO meeting on Sunday.

Could Celgene shake things up in the CAR-T market? Here's what the ASCO updates might mean for the big biotech's chances.

Three people in lab coats looking at image of DNA

Image source: Getty Images.

No need to sing the blues

The initial reaction wasn't positive after Celgene and Bluebird announced updated results from a phase 1 clinical study of CAR-T therapy bb2121 in treating late-stage relapsed/refractory multiple myeloma. As my colleague Todd Campbell noted over the weekend, Bluebird stock dropped 5% in after-hours trading after the update.

It didn't take too long for investors to realize there was no need to sing the blues about the bb2121 results, though. Bluebird stock enjoyed a nice bounce in early trading on Monday after everyone had more time to digest the new data for the CAR-T therapy.

Patients receiving bb2121 experienced progression-free survival (PFS) of 11.8 months. Some investors, though, were hoping that Celgene and Bluebird would report PFS of 15 months. While this optimistic expectation wasn't met, the updated results were still quite good. Keep in mind that the patients in the study were heavily pre-treated, with a median of seven prior regimens for treating multiple myeloma. Any significant improvement in PFS should be viewed positively.

Most important, the results didn't give any reason to think that bb2121 won't fare well in the pivotal study for the therapy. Enrollment is currently underway for this study. If all goes well, Celgene and Bluebird should submit bb2121 for FDA approval next year. Celgene projects that the drug will generate peak annual sales exceeding $2 billion.

Potential best-in-class CAR-T

At last year's ASCO meeting, Celgene didn't fully own its other promising CAR-T pipeline candidate, JCAR017. However, thanks to its acquisition of Juno Therapeutics earlier in 2018, JCAR017 is all Celgene's now. That's a good thing because the results from the experimental CAR-T therapy continue to look encouraging.

Celgene presented updated six-month safety and efficacy data from its phase 1 study of JCAR017 (also known as liso-cel) in patients with relapsed/refractory aggressive B-cell non-Hodgkin lymphoma (NHL). From an efficacy standpoint, the most notable news was the durable response rates in the group of patients meeting criteria for the pivotal study of the therapy. Patients in this group experienced a 49% overall response rate and a 46% complete response rate at six months. Across all dose levels of JCAR017, 93% of these patients in complete response at six months remained in response at the data cut-off for the study.

However, the safety results from the updated data were also very important. There was a low 1% rate of severe cytokine release syndrome, a complication caused by a large, rapid release of cytokines -- substances secreted by immune cells into the blood. In addition, there was a relatively low 13% rate of severe neurotoxicity.

Nadim Ahmed, Celgene's president of hematology and oncology, said that the updated results "continue to support a potential best-in-class CD19 CAR-T profile" for JCAR017. That's probably a fair statement at this point. Celgene has already completed enrollment in a pivotal study for the therapy targeting treatment of diffuse large B-cell lymphoma (DLBCL).

All shook up?

When Celgene CEO Mark Alles spoke last week at the Bernstein Strategic Decisions Conference, he exuded confidence about bb2121 and JCAR017. Alles said that there has "never been a better product at this stage of development" for treating multiple myeloma than bb2121. He also, like Nadim Ahmed, expressed the opinion that JCAR017 could be the best-in-class CAR-T therapy. 

Do the latest ASCO presentations mean that Celgene is set to shake up the CAR-T market? I think the answer is both yes and no. My view is that the latest updates should give investors increased confidence that Celgene is on the right track to win regulatory approvals for both bb2121 and JCAR017. I also think that both drugs will become megablockbusters over the next few years if they win approval.

On the other hand, I agree with something that Alles said in a CNBC interview on Monday. Alles noted that Celgene doesn't necessarily have to emerge as the No. 1 player in CAR-T to be successful. The opportunities for CAR-T to replace chemotherapy are enormous. There's plenty of room for multiple CAR-T therapies to help patients and make plenty of profits for drugmakers in the process.

In my view, the CAR-T party is only beginning -- and the excitement will only intensify over the next couple of years. 

Keith Speights owns shares of Celgene and Gilead Sciences. The Motley Fool owns shares of and recommends Bluebird Bio, Celgene, and Gilead Sciences. The Motley Fool has a disclosure policy.