(Reuters) - A European Medicines Agency panel on Friday recommended a conditional marketing approval for a gene therapy from Bluebird Bio Inc as a genetic blood disorder treatment, setting the stage for the U.S. biotech to win its first regulatory nod.

Final approval depends on the European Commission, which generally follows recommendations from the Committee on Human Medicinal Products (CHMP).

The decision is expected in the second quarter, Bluebird said in a statement.

The drug Zynteglo, formerly known as LentiGlobin, was developed to treat a specific group of patients with transfusion-dependent beta thalassemia (TDT).

Zynteglo is intended for patients 12 years and older who need regular blood transfusions to manage their disease and have no matching donor for a stem cell transplant, CHMP said here.

Pharmaceutical companies have been investing heavily in potentially life-changing gene therapies over the past few years, but patients and insurers expect exorbitant price tags.

Bluebird did not confirm Zynteglo’s price, but said it plans to implement a payment system that staggers costs in installments over a five-year period.

The company has previously said it believes the “intrinsic value” of the one-time infusion is about $2.1 million per patient.

Wedbush Securities analyst David Nierengarten has said in a note last month that he expected Bluebird to price much lower, at about $800,000 per patient in the European Union.

Spark Therapeutics Inc in December 2017 won the first U.S. approval for its gene therapy to treat a rare form of blindness and priced it at $850,000 per patient in the United States.

TDT patients have a genetic mutation that hampers their ability to produce hemoglobin, the protein in red blood cells that carries oxygen through the body.

Patients are diagnosed at an early age and must receive lifelong blood transfusions every few weeks.

“We basically make your bone marrow a manufacturing plant for producing hemoglobin,” Chief Executive Officer Nick Leschly told Reuters.

“We actually take out your cells, we use a virus to fix the cells and then we put the modified cells back in the body. And they go to the bone marrow and start producing what we’ve hopefully instructed those cells to do.”

Bluebird plans to file for regulatory approval of Zynteglo in the United States before the end of this year and is also testing the gene therapy in patients with sickle cell disease.

Bluebird hopes to have approvals for four new treatments, including one for multiple myeloma, by 2022, Leschly said.