Immunoglobulin Therapy Fails to Lower Serious Infections in CLL Patients

For individuals diagnosed with chronic lymphocytic leukemia (CLL), consistent use of immunoglobulin replacement therapy did not correlate with a lower likelihood of severe infections necessitating hospital admission, as indicated by research reported in Blood Advances.

Subscribe to our newsletter for the most recent science and technology news developments.

This marks the first major, real-life study tracking patients with chronic lymphocytic leukemia who consistently receive immunoglobulin therapy," stated Sara Carrillo de Albornoz, the primary researcher of the study, an epidemiologist and doctoral student at Monash University in Australia. "Considering its significant expense and inconsistent application in medical settings, this presents a crucial matter when viewed through policy, financial, and healthcare lenses.

Chronic lymphocytic leukemia (CLL), one of the most prevalent forms of leukemia among adults, interferes with the body’s ability to produce antibodies—also known as immunoglobulins—which help combat infections. Consequently, individuals diagnosed with CLL frequently face a higher vulnerability to severe and possibly fatal infections. Immunoglobulin replacement therapy is commonly administered to increase antibody levels, aiming to lower the likelihood of infections.

"Several studies backing the use of immunoglobulins to lower infection rates among individuals with blood-related cancers were conducted more than three decades ago, and treatments for chronic lymphocytic leukemia have progressed considerably since then," noted study co-author Erica Wood, AO, MD, a professor at Monash University.

Although immunoglobulins may help certain patients, there is still an essential requirement to gain a clearer understanding of the degree of their effectiveness, which individuals stand to gain the most from them, and for what duration such treatments should continue.

A group of researchers utilized integrated data from the Victorian Cancer Registry, Death Index, and Admitted Episodes Dataset, containing long-term hospital and mortality records for individuals over 18 years old who were diagnosed with chronic lymphocytic leukemia between January 1, 2008, and December 31, 2022, within Victoria, Australia. The overall number of participants in the study reached 6,217 people, where 5,464 (or 87.9%) did not receive immunoglobulin supplementation treatment, whereas 753 (representing 12.1%) got at least one administration throughout their monitoring time, averaging 6.9 years.

Throughout the 14-year observation period, for individuals who were still living, the percentage receiving immunoglobulin replacement treatment rose from 2% during the initial year post-diagnosis to 8.8% by the 14th year. Over this span, 2,191 out of 6,217 patients (35.2%) passed away, with an average survival duration from diagnosis being around ten years.

Within the entire study group, individuals who experienced a severe infection were significantly more inclined to start immunoglobulin replacement therapy within 30 days after their illness, occurring at a rate of 0.075 per person-month (a measure indicating how often an event occurs among people being monitored over one month), as opposed to only 0.001 per person-month for those who did not have a major infection. Out of the 753 patients who initiated immunoglobulin replacement therapy, 346 (or 45.9%) passed away during the observation period, with a median survival time of about six years since starting treatment.

In line with the broader study group, individuals receiving immunoglobulin replacement therapy who were admitted to the hospital due to a severe infection within the last month exhibited a greater 30-day fatality risk per person-month than those without such infections (0.090 versus 0.008) — underscoring the major role infections play as a primary cause of death among people with chronic lymphocytic leukemia.

Although immunoglobulin replacement therapy became more widely used during the study period, the rate of severe infections needing hospitalization rose from 1.9% to 3.9%. Researchers observed that patients who consistently took immunoglobulins had a notably greater risk of infection during their treatment compared to when they were not on the therapy (0.056 versus 0.038 infections per person-month). For those undergoing regular immunoglobulin treatments, 46.9% continued the therapy for between one and five years, while 23.5% stayed on treatment longer than five years, depending on their follow-up and survival status.

Besides not observing a decrease in infection rates or hospital admissions among patients who received immunoglobulins, we noticed that several remained on this treatment for lengthy durations," stated Dr. Wood. "It's crucial that we examine how long these individuals stay on the therapy and the reasons behind it to prevent excessive, ongoing, and costly use of a resource that is scarce worldwide.

Intravenous administration of immunoglobulins is commonly performed in hospitals, though home-based subcutaneous infusions are becoming more common. The expensive nature of this treatment stems mainly from its complicated production method and the regularity of required doses; individuals diagnosed with chronic lymphocytic leukemia often receive intravenous immunoglobulins once each month. In Australia, where this research was conducted, the expense of immunoglobulin is entirely covered by the government, yet in the U.S. and several other nations, the economic strain can be considerable.

This treatment's cost, the strain it places on patients, and the usage and infection trends we have seen clearly highlight the need for improved guidance regarding the administration of immunoglobulins," stated Ms. Carrillo. "While there are standards for accessing publicly funded treatment within this group in Australia, specific medical guidelines remain absent.

The research includes certain constraints due to its retrospective design, such as possible selection bias and missing information, especially regarding clinical predictive indicators, illness intensity, and cancer therapy. Furthermore, notable variations existed at the start of the study among the different patient groups being compared, including those who received immunoglobulin treatments and those who did not, as well as patients who got them consistently versus occasionally.

Scientists are conducting ongoing follow-up research, which includes a clinical study evaluating immunoglobulins versus antibiotics for preventing infections in individuals diagnosed with chronic lymphocytic leukemia, non-Hodgkin lymphoma, and multiple myeloma. Additionally, they are investigating the expenses related to immunoglobulin treatments and severe infections among patients with hematologic malignancies.

More information: Use of immunoglobulins, patient survival rates, and infectious disease results among individuals diagnosed with chronic lymphocytic leukemia, Blood Advances (2025). DOI: 10.1182/bloodadvances.2025015867

Supplied by the American Society of Hematology

This narrative first appeared on Medical Xpress .