SUMMARY: The FDA on November 9, 2017 granted regular approval to ADCETRIS® (Brentuximab vedotin), for the treatment of adult patients with primary cutaneous Anaplastic Large Cell Lymphoma (pcALCL) or CD30-expressing Mycosis Fungoides (MF), who have received prior systemic therapy. Primary Cutaneous T Cell Lymphoma (CTCL) is a type of Non Hodgkin Lymphoma and includes a spectrum of diseases that primarily involve the skin, but may ultimately involve lymph nodes, blood and visceral organs such as spleen, liver and lungs. The prevalence in the US is approximately 16,000-20,000 patients and the incidence is higher in blacks than Caucasians or Asians. It is more common in men, and the median age at diagnosis is 50 years. Mycosis Fungoides/Sezary Syndrome is the most common type of CTCL accounting for 44% of cases. Patients with Stage I disease have an excellent prognosis. However for those with advanced disease, durable responses are rare with present available therapies and outcomes are poor.
ADCETRIS® (Brentuximab vedotin) is an Antibody-Drug Conjugate (ADC) that targets CD30. ADCETRIS® consists of the anti-CD30 monoclonal antibody SGN-30 conjugated to the cytotoxic agent, MonoMethyl Auristatin E (MMAE) via a peptide linker. When administered intravenously, ADCETRIS® is internalized by CD30 expressing tumor cells, causing the release of MMAE into the cytosol through the enzymatic cleavage of the peptide linker.
The FDA approval was based on international, multicentre, open-label, randomized, phase III trial (ALCANZA), which enrolled 131 previously treated patients with CD30-positive Mycosis Fungoides (MF) or primary cutaneous Anaplastic Large Cell Lymphoma (pcALCL). Patients with MF were required to have received at least one prior systemic therapy and those with pcALCL were required to have prior radiation therapy or at least one systemic therapy. Patients were randomly assigned (1:1) to receive ADCETRIS® 1.8 mg/kg IV once every 3 weeks, for up to 16 cycles (N=66), or physician's choice of Methotrexate 5-50 mg orally once per week or Bexarotene 300 mg/m2 orally once daily for up to 48 weeks (N=65). There were more pcALCL patients with extracutaneous disease in the ADCETRIS® group (44% versus 27%). The Primary endpoint was the proportion of patients achieving an Objective Response Rate lasting at least 4 months (ORR4). Secondary outcome measures included Complete Response (CR) rate, Progression Free Survival (PFS), and reduction in the burden of symptoms during treatment.
At a median follow-up of 22.9 months, the proportion of patients achieving an objective global response lasting at least 4 months was 56.3% with ADCETRIS® versus 12.5% with physician's choice of treatment (P<0.0001). The CR rate in the ADCETRIS® group was 16% versus 2% in the physicians choice group (P=0.007). The median PFS was 16.7 months in the ADCETRIS® arm versus 3.7 months in the physicians choice arm (HR=0.27; P<0.001). The most common adverse reactions in those patients receiving ADCETRIS®: were anemia, neutropenia, peripheral neuropathy, nausea, diarrhea and fatigue. The most common adverse event leading to treatment discontinuation was peripheral neuropathy.
It was concluded that treatment with ADCETRIS® resulted in significant improvement in Objective Response Rate and Progression Free Survival, among patients with advanced CD30-positive Mycosis Fungoides or primary cutaneous Anaplastic Large Cell Lymphoma, fulfilling an unmet need for this patient group. Brentuximab vedotin or physician's choice in CD30-positive cutaneous T-cell lymphoma (ALCANZA): an international, open-label, randomised, phase 3, multicentre trial. Prince HM, Kim YH, Horwitz SM, et al. Lancet. 2017;390:555-566.