Are orphan drugs still factoring into the growth strategies of the pharmaceutical majors? Which recent deals stand out? DCAT Value Chain Insights takes an inside look at the companies, products, and deals. 

By Patricia Van Arnum, Editorial Director, DCAT, pvanarnum@dcat.org

Rare diseases and deal-making
The large pharma companies continue to invest in rare-disease drugs through acquisitions, representing a specific move in dedicated rare-disease drug portfolios or part of their larger therapeutic focus areas. Gilead Sciences, Eli Lilly and Company, Novartis, Sanofi, and GSK are among the large pharma companies with recent acquisitions are outlined below.

Gilead Sciences’ $7.8-billion acquisition of Arcellx, which was completed this week (April 30, 2026) nets Gilead Arcellx’s lead pipeline candidate, anitocabtagene autoleucel (anito-cel), an investigational B-cell maturation antigen (BCMA)-directed CAR T-cell therapy for treating relapsed or refractory multiple myeloma. Multiple myeloma is a rare form of cancer characterized by excessive production and improper function of certain cells (plasma cells) found in the bone marrow. Anito-cel holds both orphan drug and fast-track designations by the US Food and Drug Administration (FDA). The biologics license application for anito-cel is as a fourth-line treatment for patients with relapsed or refractory multiple myeloma. The BLA has been accepted by FDA with an anticipated Prescription Drug User Fee Act (PDUFA) action date of December 23, 2026. The cell therapy is designed to improve upon existing therapies with a unique, compact binder (D-Domain) aiming for high efficacy and improved safety (less neurotoxicity).

Another deal in the multiple myeloma space is Eli Lilly and Company’s pending acquisition of Kelonia Therapeutics, a Boston-based clinical-stage bio/pharmaceutical company specializing in in vivo gene delivery, in a $7-billion deal ($3.25 billion upfront and $3.75 billion in milestone payments). Kelonia has developed a proprietary in vivo gene-placement system, iGPS, which uses specially engineered lentiviral-based particles designed to enter T-cells inside the body to allow the patient to generate chimeric antigen receptor T-cell (CAR-T) therapies. Specifically, in vivo gene delivery technology uses an advanced lentiviral vector particle harboring envelope modification to improve in vivo gene transfer efficiency and tropism molecules to facilitate tissue-specific delivery. Kelonia’s lead program, KLN-1010, currently in Phase I development for relapsed/refractory multiple myeloma, is an investigational, one-time intravenous gene therapy that generates anti-B-cell maturation antigen (BCMA) CAR-T cells, targeting the BCMA protein expressed on the surface of multiple myeloma cells. The deal is expected to close in the second half of 2026. 

Also, this week, Eli Lilly and Company reported it has agreed to acquire Ajax Therapeutics, a bio/pharmaceutical company developing JAK inhibitors for treating myeloproliferative neoplasms, a group of rare, chronic blood cancers, for $2.3 billion. JAK inhibitors are a class of targeted immunomodulatory medications that block specific enzymes (JAK1, JAK2, JAK3, TYK2) to reduce inflammation and manage autoimmune disorders. Ajax’s lead asset, AJ1-11095, is an investigational, once-daily oral Type II JAK2 inhibitor currently being evaluated in a Phase I clinical trial with first proof-of-concept clinical data to be presented later in 2026. It is being evaluated for treating myelofibrosis in patients who have previously been treated with a Type I JAK2 inhibitor. AJ1-11095 was designed as a selective Type II JAK2 inhibitor to provide deeper and more durable efficacy than existing JAK2 inhibitors and a option for those patients who become resistant to Type I JAK2 inhibitors, according to information from Lilly.

In March (March 2026), Novartis completed its $12-billion acquisition of Avidity Biosciences, a bio/pharmaceutical company developing RNA therapeutics and antibody oligonucleotide conjugates (AOCs) for treating rare genetic neuromuscular diseases. The AOC platform combines the tissue specificity of monoclonal antibodies with oligonucleotide payloads to target delivery to previously hard-to-reach muscle cells, according to information from Novartis. 

The acquisition provides Novartis with three late-stage drug candidates: (1) delpacibart etedesiran for treating myotonic dystrophy Type 1, a rare progressive neuromuscular disorder; (2) delpacibart braxlosiran for treating facioscapulohumeral muscular dystrophy,a rare hereditary disorder causing loss of muscle function and progressive disability; and (3) delpacibart zotadirsen for treating Duchenne muscular dystrophy, an early-onset disease marked by progressive muscle damage and reduced life expectancy. 

Also, last month (April 2026), GSK completed its $950-million acquisition of 35Pharma, a clinical-stage bio/pharmaceutical company, which netted GSK HS235, an investigational medicine that has completed Phase I healthy volunteer clinical trials with studies to start imminently (as reported on April 15, 2026) in two forms of pulmonary hypertension: pulmonary arterial hypertension (PAH), which refers to a group of rare diseases where the blood pressure in the arteries of the lungs and pulmonary hypertension due to heart failure with preserved ejection fraction, not a rare disease but a form of heart failure frequently associated with pulmonary hypertension.

Another key deal is Sanofi’s $9.5-billion acquisition ($9.1 billion upfront and up to $400 million in milestone payments) of Blueprint Medicine, which was completed last year (2025) in move for Sanofi to boost its rare-disease drug portfolio. A key asset is Ayvakit (avapritinib), which is approved for treating adults with indolent or advanced systemic mastocytosis, a rare blood cancer, and specific gastrointestinal stromal tumors.