Analysis of Severe Infections in Patients Receiving Chemoimmunotherapy for Chronic Lymphocytic Leukemia

Chronic lymphocytic leukemia (CLL) often is associated with impaired immunity. Furthermore, many patients with CLL receive chemoimmunotherapy, which can cause additional issues with the immune system. Thus, patients with CLL are prone to cytopenia, neutropenia, and infections.

At the all-virtual 62nd ASH Annual Meeting & Exposition, researchers presented data from a study that examined incidence, characteristics, and outcomes of infections during and after therapy for CLL.

The researchers pooled data on 2,291 patients (median age, 64 years) who received at least one dose of chemoimmunotherapy as part of five phase II or III clinical trials from the German CLL Study Group. Information gathered included clinical, laboratory, genetic, and event-related data.

The study team defined an infection as severe if it was grade 3-5 according to Common Terminology Criteria. They deemed an infection to be related to CLL treatment if the infection started anytime between initiation of therapy and four weeks after treatment completion.

Overall, the analysis identified 274 severe grade infections in 229 patients (10%):

  • 189 patients (82.5%) had grade 3 infection.
  • 22 (9.6%) patients had grade 4 infections.
  • 18 (7.9%) patients died from infectious complications.

Median time to severe infection from treatment initiation was 1.8 months, and the median number of infectious episodes per patient was one (range, 1-4 infections).

Of the 229 patients with infection:

  • 31 (13.5%) had bacterial infection
  • 35 (15.3%) had viral infection
  • 5 (2.2%) had fungal infection
  • 172 (75.1%) had unspecified infection

The researchers found no associations between infection rates and any of the following: age, gender, Eastern Cooperative Oncology Group performance status score, creatinine clearance, immunoglobulin levels pre-treatment, response to first-line treatment, or molecular or cytogenetic characteristics.

The analysis also showed that patients who had severe infections had significantly shorter overall survival (OS) compared with patients who did not develop severe infections. Median rates of OS four weeks after completion of treatment were 73.7 months versus 97.3 months, respectively.

“Prognosis for patients with CLL who receive first-line treatment with immunochemotherapy is influenced by severe infections,” said lead presenter Othman Al-Sawaf, MD, of the University of Cologne Department of Internal Medicine and Center of Integrated Oncology in Germany. “Due to their vulnerability, careful management of infectious complications in [patients with] CLL is warranted.”