FDA Approves Larger Nelarabine Vial for Some Leukemias and Lymphomas

The U.S. Food and Drug Administration (FDA) has approved a larger vial size of nelarabine injection (SH-111) for the treatment of T-cell acute lymphoblastic leukemia (T-ALL) and T-cell lymphoblastic lymphoma (T-LBL), according to a news release from Shorla Oncology. The newly approved 375-milligram/75-milliliter vial is designed to address long-standing dosing challenges associated with body size differences across age groups.

Although the approval does not change how nelarabine works or who it is prescribed for, clinicians and pharmacists may now have greater flexibility when preparing doses, potentially simplifying treatment administration for patients living with these aggressive blood cancers.

“We are delighted to offer this new larger vial size of nelarabine injection to better serve adult and pediatric patients with T-cell leukemia and lymphoma,” said Sharon Cunningham, CEO and co-founder of Shorla Oncology. “Both adult and pediatric patients have differing dose needs, which can make treatment preparation complex. With this FDA approval, we hope to support healthcare providers in delivering care more efficiently… and improving precision in managing these types of aggressive blood cancers.”

Why the larger nelarabine vial matters

T-cell acute lymphoblastic leukemia is an aggressive blood cancer in which immature T cells, a type of white blood cell, grow uncontrollably in the bone marrow and blood. T-cell lymphoblastic lymphoma is closely related and involves similar cancerous cells but typically presents as tumors in lymph nodes or other tissues.

These diseases affect both children and adults, although treatment approaches often differ due to variations in body size, metabolism, and tolerance to therapy. Pediatric T-ALL is most commonly diagnosed around age nine, whereas adult cases tend to require higher overall doses of chemotherapy.

Despite advances in treatment, relapsed or refractory T-ALL and T-LBL remain challenging to manage, underscoring the importance of optimizing every aspect of care, including drug preparation and delivery.

Nelarabine is a chemotherapy drug used in patients with T-ALL or T-LBL whose disease has not responded to, or has returned after, at least two prior chemotherapy regimens. Until now, nelarabine was available in a smaller 250-milligram vial, which sometimes required multiple vials to meet an individual patient’s dose. The newly approved 375-milligram vial allows for more tailored dosing based on a patient’s body surface area, a calculation commonly used in cancer care to determine chemotherapy doses. For many patients, especially children, this change may allow clinicians to prepare doses more precisely using fewer vials.

Shorla Oncology noted that this approval represents the company’s second FDA approval for nelarabine injection, both using the same formulation.

How nelarabine is used in treatment

Nelarabine injection is classified as a nucleoside metabolic inhibitor, a type of chemotherapy that interferes with cancer cell DNA replication. It is approved for patients aged one year and older whose T-ALL or T-LBL has not responded to at least two previous chemotherapy regimens. The drug carries a boxed warning for neurologic side effects, meaning clinicians closely monitor patients for symptoms such as drowsiness, confusion, numbness, weakness, or other nervous system changes. If moderate or severe neurologic side effects occur, treatment is typically stopped.

The FDA approval of the larger vial does not alter dosing schedules or safety requirements but instead focuses on improving how doses are prepared and administered.

The new vial size may be particularly helpful for pediatric patients, who often require smaller, more individualized doses. For example, children with T-ALL have an average body surface area of approximately 1.07 square meters, translating to a typical nelarabine dose of around 696 milligrams. The larger vial may allow clinicians to reach this dose more efficiently with fewer vials.

Adult patients, who generally have a larger body surface area averaging approximately 1.7 square meters, often require doses exceeding 2,500 milligrams. For this group, the larger vial may streamline preparation and reduce the complexity of dosing.

Safety and practical considerations

Nelarabine remains associated with well-documented side effects. In adults, common adverse reactions include low blood counts, fatigue, nausea, shortness of breath and neurologic symptoms such as dizziness or numbness. In pediatric patients, low blood counts and headaches are among the most frequently reported side effects.

Patients receiving nelarabine are advised to avoid driving or operating heavy machinery if they experience drowsiness and to discuss pregnancy, breastfeeding and kidney or liver conditions with their care team.

What this approval means for patients

Although the FDA approval of a larger nelarabine vial does not represent a new treatment, it reflects a meaningful step toward improving the day-to-day delivery of care for patients with T-ALL and T-LBL. By enabling more precise dosing and potentially reducing treatment complexity, this update may help clinicians focus on what matters most: delivering effective therapy as safely and efficiently as possible.

Patients are encouraged to speak with their oncology team about how nelarabine is used in their treatment plan and whether this update may affect their care.

Editor's note: This article is for informational purposes only and is not a substitute for professional medical advice, as your own experience will be unique. Use this article to guide discussions with your oncologist. Content was generated with AI and reviewed by a human editor.

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