Ofatumumab is a fully human, high-affinity antibody targeted at the CD20 molecule in the cell membrane of B-cells and is being developed under a worldwide co-development and commercialization agreement with GlaxoSmithKline (GSK).
Ofatumumab has received accelerated approval from the US Food and Drug Administration for use in patients in the US with chronic lymphocytic leukemia (CLL) that is refractory to fludarabine and alemtuzumab under the trade name Arzerra®. The approval is based on results from a pivotal study in which 42% of patients with CLL who were refractory to both fludarabine and alemtuzumab (two therapies used in treating CLL) responded to treatment with ofatumumab. These patients had a median duration of response of 6.5 months. The most common adverse reactions (≥10%) seen were neutropenia, pneumonia, pyrexia, cough, diarrhea, anemia, fatigue, dyspnea, rash, nausea, bronchitis, and upper respiratory tract infections. The most common serious adverse reactions seen were infections (including pneumonia and sepsis), neutropenia, and pyrexia.
GSK has added Arzerra to its expanding patient assistance program, Commitment to Access. This program assists eligible patients in the US, with or without insurance, with paying for cancer medicines. For more information about the program, visit www.CommitmentToAccess.com or call 1-8ONCOLOGY1 (1-866-265-6491).
Genmab and GSK also submitted a Marketing Authorization Application (MAA) to EMEA on February 5, 2009 and EMEA has confirmed that the MAA is valid.
Ofatumumab is a monoclonal antibody that causes the body's immune response to fight against normal and cancerous B-cells. Ofatumumab attaches to the small and large loop epitopes on a molecule called CD20, which is found on the surface of B-cells, the type of cell which becomes cancerous in CLL.
The CD20 molecule appears to act as a calcium ion channel and regulate early steps in B lymphocyte activation. The molecule is not shed from the cell surface and is not internalized upon antibody binding. CD20 is found on over 90% of B-cell lymphomas, as well as other lymphoid tumors of B-cell origin. In types of cancer such as these, the B-cells can over-proliferate and treatment is needed to reduce their number.
B-cells are also crucial pathogenic elements in the induction and pathogenesis of RA. As B-cells are involved in various cellular interactions with immune cells, B-cell depletion after ofatumumab treatment may affect RA disease activity.
Follicular NHL is a subgroup of NHL and is the second most common lymphoma in the US and Europe, accounting for 11 to 35% of all NHL.
Ongoing Clinical Studies
Phase III Pivotal Study
A pivotal study to treat follicular NHL patients who are refractory to rituximab in combination with chemotherapy or to rituximab given as maintenance treatment is ongoing. Top-line results from the study were reported in August 2009. A total of 116 patients were treated in the study, including 30 patients treated with 500 mg ofatumumab and 86 patients treated with 1000 mg of ofatumumab. The patients in the study were highly refractory. Forty-nine percent of patients were refractory to their last chemotherapy treatment. Patients in the study had previously received a median of 4 prior treatment regimens.
The overall response rate (ORR) in the 1000 mg treatment arm was 10%, including one complete response and 8 partial responses. In addition, 50% (43) of patients in the 1000 mg treatment arm had stable disease. The overall response rate in the total population was 11%.
The ORR among patients who were refractory to prior rituximab monotherapy (n=27) was 22%. For patients considered refractory to rituximab in combination with chemotherapy the response rate was 7% and among patients considered refractory to rituximab maintenance the response rate was 9%. The median duration of response in the 1000 mg treatment arm was 6 months and the progression free survival was 6 months.
There were no unexpected safety findings reported during treatment and within 30 days after last infusion. The most common adverse events (greater than 10%) were rash, urticaria, pruritus, fatigue, nausea, pyrexia and cough.
Patients in this study failed to achieve at least a partial response to rituximab in combination with chemotherapy, had disease progression while on rituximab or had disease progression following a response within 6 months of the last dose of rituximab. Patients received one infusion of 300 mg of ofatumumab followed by 7 weekly infusions of 500 mg or 1000 mg of ofatumumab. Disease status was assessed every 3 months until month 12, then every 6 months until month 24. Patients will be followed every 6 months thereafter until month 60. The protocol was amended in 2007 to discontinue enrollment in the 500 mg dosing allowing full recruitment at 1000 mg.
The objective of the study was to determine the efficacy and safety of ofatumumab in rituximab refractory follicular NHL. The primary endpoint of the study was objective response as measured over a 6 month period from start of treatment and assessed by an Independent endpoints Review Committee according to the standardized criteria for NHL. Secondary endpoints include duration of response and safety.
Phase III Bendamustine Combination Study
A Phase III study of ofatumumab plus bendamustine versus bendamustine monothearpy to treat patients with indolent B-cell non-Hodgkin's lymphoma (NHL) who did not respond to rituximab or progressed on a rituximab-containing regimen during or within six months of the last rituximab treatment has not yet begun recruitment.
A total of 338 patients in this open label study will be randomized to receive either ofatumumab in addition to bendamustine or bendamustine alone. Each group will receive up to eight cycles of bendamustine while the combination group will be given ofatumumab on day one of each cycle. Once patients in the combination group have completed bendamustine therapy, they will continue to receive ofatumumab monthly until 12 doses have been given. The primary endpoint of the study is progression free survival.
Phase II CHOP Combination Study
Top-line results from a Phase II study of ofatumumab in combination with cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) in patients with previously untreated follicular NHL were reported in August 2009. A total of 58 patients were treated in the study. The overall response rate (ORR) in patients treated with 500 mg of ofatumumab (n=29) was 90%, including 24% complete remissions (CR), and 45% complete remissions/unconfirmed (CRu). In patients treated with 1000 mg of ofatumumab (n=29), the ORR was 100% including 38% CR, and 17% CRu.
There were no unexpected safety findings reported during treatment and within 30 days after last infusion. The most common adverse events of grade 3 or 4 (greater than 10 percent) were leucopenia and neutropenia. No events of sepsis or pneumonia were observed, and no deaths reported in the trial.
Patients in this open label study were randomized into two dose groups of 29 patients each. Patients were to receive 300 mg of ofatumumab at the first infusion, followed by 5 infusions of either 500 or 1000 mg of ofatumumab every 3 weeks in combination with 6 cycles of CHOP. Disease status is measured prior to the fourth cycle, at three months following the last treatment and then every three months until month 12, and every six months thereafter until 24 months or initiation of alternative treatment. Treatment response was assessed according to the 1999 standardized response criteria for NHL by an Independent endpoints Review Committee.
The objective of the study is to determine the efficacy of two dose regimens of ofatumumab in combination with CHOP in previously untreated follicular NHL patients. The primary endpoint in the study was objective response from start of treatment until 3 months after last administration of ofatumumab.
Phase I Study in Japan
An open-label study including a maximum of 12 patients with relapsed/refractory follicular NHL and at least 1 CLL patient has been completed. Patients were divided into 2 cohorts of 3 or 6 patients. Under the study protocol, patients received one infusion of ofatumumab at 300 mg followed by seven weekly infusions of 500 or 1000 mg of ofatumumab. Safety at the 500 mg dose level of ofatumumab was examined before progressing to the 1000 mg dose level. The primary objective of the study was to evaluate the safety and tolerability of ofatumumab in Japanese relapsed/refractory follicular NHL and CLL patients. The primary endpoint of the study was safety.
Planned Clinical Studies
Phase II Retreatment and Maintenance Study
In August 2008, Genmab announced plans to initiate a study examining the retreatment and maintenance treatment of refractory follicular NHL patients who participated in the ongoing Phase III NHL study and had disease progression following at least 6 months objective response to or stable disease on ofatumumab. Eligible patients will receive one infusion of ofatumumab at 300 mg followed by 7 once weekly infusions at 1000 mg. Maintenance treatment will consist of one 1000 mg infusion every two months for two years. The primary objective of this study is to evaluate the safety of ofatumumab retreatment and maintenance treatment.
Chronic Lymphocytic Leukemia
CLL is the most common leukemia and one of the most common malignant lymphoid diseases in the Western world. Globally, leukemia accounts for some 300,000 new cases each year (2.8% of all new cancer cases) and 222,000 deaths.
Ongoing Clinical Studies
Phase III Pivotal Study
A Phase III pivotal study with ofatumumab to treat patients with refractory B-cell CLL is ongoing. A total of 220 patients have been enrolled in the study. The two main patient populations to be examined in the study are: patients who are refractory to both fludarabine and alemtuzumab (double refractory; DR) and fludarabine refractory patients who are considered inappropriate candidates for alemtuzumab due to bulky tumor in their lymph nodes (bulky fludarabine refractory; BFR). Each group consists of approximately 100 patients and will be analyzed separately.
Patients in the pivotal trial received 8 weekly infusions of ofatumumab, followed by 4 monthly infusions of ofatumumab. Patients received 300 mg of ofatumumab at the first infusion and 2000 mg of ofatumumab at each subsequent infusion. Disease status will be assessed every 4 weeks until week 28 and then every 3 months until disease progression or month 24.
The objective of the study is to evaluate the efficacy and safety of ofatumumab and the primary endpoint is objective response over a 24 week period from start of treatment. The responses will be assessed by an Independent Endpoints Review Committee according to the NCI Working Group guidelines.
Genmab and GSK reported results from an interim analysis of the study in July and December 2008. This study formed the basis for the accelerated approval of ofatumumab for CLL refractory to fludarabine and alemtuzumab. (Click here to read prescribing information.)
Ofatumumab was generally well tolerated by CLL patients in the study and there were no unexpected safety findings. The most common adverse event seen was infusion related reactions which were mostly mild to moderate in severity. The most common serious adverse events (Grade 3 or 4) were infections (25 percent in DR; 25 percent in BFR), including 1 case of progressive multifocal leukoencephalopathy (PML) in a patient with progressive disease. Early death (within eight weeks from start of treatment) occurred in four patients (7 percent) in the DR group and two patients (3 percent) in the BFR group. None of the 33 patients tested for human anti-human antibodies (HAHA) demonstrated their presence at 12 months.
Phase II FC Combination Study
A Phase II study of ofatumumab in combination with fludarabine and cyclophosphamide (FC) to treat CLL in previously untreated patients is ongoing and top-line results were reported in August 2009. A total of 61 patients were treated in the study. Treatment response was assessed using the 1996 National Cancer Institute Guidelines. The complete remission rate was 32% in patients who received 500 mg of ofatumumab (n=31) and 50% in patients who received 1000 mg of ofatumumab (n=30). The overall response rate was 77% in the 500 mg treatment group and 73% in the 1000 mg treatment group.
There were no unexpected safety findings reported during treatment and within 30 days after last infusion. The most common adverse event reported was neutropenia at 48%. Other common adverse events (greater that 15 percent) were nausea, leukopenia, rash, vomiting, pyrexia, headache and thrombocytopenia. The number of patients, who experienced adverse events, including serious adverse events, was similar between the two dose groups. One death was reported and was judged by the investigator as unrelated to ofatumumab.
Patients in this open label study were randomized into two treatment groups. Each patient was to receive one infusion of 300 mg of ofatumumab in combination with FC followed by 5 monthly infusions of either 500 or 1000 mg of ofatumumab in combination with FC. Disease status was measured every 4 weeks until week 24 and every 3 months thereafter until disease progression or 24 months. Treatment response was assessed according to the 1996 National Cancer Institute Working Group guidelines by an Independent endpoints Review Committee. Patients not having progressed on their disease at 24 months will be followed for disease progression at 6 month intervals until 60 months.
The objective of the study was to determine the efficacy of ofatumumab in combination with FC in previously untreated CLL patients. The primary endpoint was complete remission rate from start of treatment until 3 months after last infusion.
Phase III Front Line Chlorambucil Combination Study
An open-label, parallel-arm study including 444 patients with previously untreated CLL was initiated in November 2008. Patients in the study will be randomized to receive ofatumumab in combination with chlorambucil or chlorambucil alone. Patients receiving ofatumumab in combination with chlorambucil will receive one infusion of ofatumumab at 300 mg, one infusion at 1000 mg a week later, followed by up to 11 monthly infusions at 1000 mg. Patients will be evaluated for disease status one month following last treatment then every 3 months for 5 years. The primary objective of the study is to evaluate the progression free survival of ofatumumab in combination with chlorambucil therapy versus chlorambucil therapy alone for the treatment of front line CLL.
Phase III FC Combination Study
A Phase III study of ofatumumab in combination with FC to treat second line CLL is ongoing. The open label study will include 352 patients with relapsed CLL. Patients will be randomized to receive either ofatumumab (initial dose at 300 mg, then 6 monthly doses at 1000 mg) in combination with FC or FC alone. Disease status will be measured monthly and patients will be followed one month and then every 3 months following treatment for 5 years to evaluate survival and disease status. The primary objective of the study is to evaluate progression free survival (PFS) of oaftumumab in combination with FC therapy versus FC therapy alone for the treatment of relapsed CLL. The primary endpoint of the study is PFS from randomization until disease progression or death.
Phase III Maintenance Study
This is a Phase III open-label, two-arm, 1:1 randomized study of ofatumumab or no further treatment in 532 patients with complete or partial responses after remission induction treatment for relapsed CLL. The patients in the ofatumumab arm will receive infusions (1000 mg) every eight weeks for up to two years. The primary endpoint of the study is progression free survival.
Phase II Retreatment and Maintenance Study
In August 2008, Genmab announced plans to initiate a study to examine the retreatment and maintenance treatment of refractory CLL patients who participated in the ongoing Phase III CLL study and had disease progression following at least an objective response or stable disease during a 24 week treatment period of ofatumumab. Eligible patients will receive one infusion of ofatumumab at 300 mg followed by 7 once weekly infusions at 2000 mg. Maintenance treatment will consist of 24 once monthly infusions of 2000 mg of ofatumumab. The primary objective of this study is to estimate the proportion of objective responses over 52 weeks.
Phase II Study in Japan
An open-label study including a maximum of 10 patients with previously treated CLL. Patients will receive a first dose of 300 mg before 7 weekly infusion of 2000 mg, followed by 4 infusions of 2000 mg. at every 4 weeks. The primary objective of the study is to evaluate tolerability and assess overall response rate in CLL patients.
Rheumatoid Arthritis
RA is a systemic inflammatory disease which affects 0.8-1.0% of all populations.
Ongoing Clinical Studies
Phase III Program
In November 2007, Genmab announced the initiation of a Phase III program with ofatumumab to treat RA. The program commenced with two studies (GEN410/OFA110635 and GEN411/OFA110634, described below) which will be conducted outside the US, in two distinct patient populations.
Each study will evaluate the efficacy of ofatumumab in reducing the clinical signs and symptoms in RA patients after a single course of ofatumumab and are comprised of a 24 week double-blind period followed by a 120 week open-label period during which re-treatment will be studied. The primary endpoint in each study is ACR20 at 24 weeks.
GEN410/OFA110635 Phase III Methotrexate Refractory Study
A total of 260 patients who had an inadequate response to methotrexate therapy have been enrolled in the study. In the double-blind period, patients were randomized to receive two 700 mg doses of ofatumumab or placebo two weeks apart in addition to background methotrexate. Rescue treatment with nonbiologic disease modifying anti-rheumatic drugs (DMARDs) was allowed from week 16 in the double-blind period. Patients who completed the double-blind period without receiving rescue treatment continued into the open-label period of the study. Re-treatment will be studied starting at week 24. Disease status will be measured every 4 weeks during the double-blind period and every 8 weeks during the open-label period.
Preliminary top-line results from the study were reported in July 2009. At week 24, the ACR20 response rate was significantly greater for RA patients on ofatumumab (n=129) than on placebo (n=131) with a 50% response rate in patients receiving ofatumumab, compared to 27% for patients on placebo (p<0.001). All key secondary endpoints were significant (p≤0.001). There were no unexpected safety findings. The most common adverse events in the ofatumumab treated patients (>5%) were rash, urticaria, nasopharyngitis, pruritus, throat irritation and hypersensitivity. Other than nasopharyngitis, these events generally occurred within 24 hours of the first infusion. One death, judged by the investigator as unrelated to ofatumumab was reported in the 24 week study period.
GEN411/OFA110634 Phase III TNF-alpha Refractory Study
Approximately 250 patients who had an inadequate response to TNF-alpha antagonist therapy will be enrolled. In the double-blind period, patients will be randomized to receive two 700 mg doses of ofatumumab or placebo two weeks apart in addition to background methotrexate. Rescue treatment with nonbiologic disease modifying anti-rheumatic drugs (DMARDs) will be allowed from week 16 in the double-blind period. All patients who complete the double-blind period without receiving rescue treatment will continue into the open-label period of the study. Re-treatment will be studied starting at week 24. Disease status will be measured every 4 weeks during the double-blind period and every 8 weeks during the open-label period.
Phase II RA Retreatment Study
A Phase II study of ofatumumab in RA patients who previously participated in the previous Phase II study is ongoing.
Phase I/II Subcutaneous Study
A Phase I/II study to evaluate a subcutaneous route of administration of ofatumumab in RA patients, stable on methotrexate has been initiated. The study, which consists of two parts and includes approximately 70 patients, will be conducted by GlaxoSmithKline.
The objective and primary endpoint of Part A of the study is to characterize the safety and tolerability of ofatumumab when administered subcutaneously. The primary endpoint for Part B is to characterize the pharmacokinetics/pharmacodynamics of subcutaneous dosing. Patients in both Part A and Part B are allowed to continue a stable dose methotrexate therapy.
Part A will be a randomized, single-blind, placebo controlled, repeat dose, parallel group, dose-range finding study of approximately 40 patients. Administration of ofatumumab for Part A will occur in a hospital based unit in order to ensure safety.
Part B will be a blinded, randomized, placebo controlled study. On the basis of findings in Part A of the study selected doses will be taken forward for administration in Part B. Dosing for Part B is planned to be conducted on an outpatient basis.
Previous Clinical Studies
Phase II Study
The Phase II trial is an extension of a previous Phase I/II trial and included 200 additional patients randomized into four treatment groups. In each group, 50 patients received two infusions of 300, 700, or 1000 mg of ofatumumab or placebo, given two weeks apart. Patients receiving a stable dose of methotrexate between 7.5 and 25 mg per week at the time of screening continued with it. Patients were followed for 24 weeks to evaluate safety and efficacy and then every 12 weeks until B-cell counts return to baseline levels.
Positive primary efficacy data from the study was presented at EULAR 2007. A total of 225 patients with active RA who have previously failed one or more disease-modifying anti-rheumatic drugs (DMARDs) were enrolled in the Phase II study. In the intention-to-treat study population, comprising 224 patients, ACR20 was achieved by 46% of all patients receiving ofatumumab, ACR50 was achieved by 24% and ACR70 was achieved by 6% of ofatumumab patients compared to 15%, 5% and 0% in the placebo group. Evaluated by dose groups, an ACR20 response was obtained by 41% (p=0.002), 49% (p<0.001) and 46% (p<0.001) of patients receiving 300 mg, 700 mg and 1000 mg of ofatumumab. An ACR50 response was obtained by 19%, 26% and 26% of patients receiving the varying doses of ofatumumab, with 9%, 4% and 6% obtaining an ACR70 response. These scores indicate a 20%, 50% or 70% improvement respectively in the number of swollen and tender joints, as well as improvements in other disease-activity measures.
In the subgroup of patients receiving concomitant stable doses of methotrexate, comprising 178 patients, results across the three dose levels of ofatumumab studied showed that an ACR20 response was obtained by 42% (p=0.006), 56% (p<0.001) and 50% (p=0.001) of patients in the 300 mg, 700 mg and 1000 mg dose groups, respectively compared to 16% in the placebo group. An ACR50 response was obtained by 21%, 26% and 26% of patients receiving the varying doses of ofatumumab, with 8%, 2% and 5% obtaining an ACR70 response. The corresponding responses for the placebo group were 7% and 0%.
At 24 weeks, the patients’ immune responses to study medication (ofatumumab or placebo) were also evaluated by testing for the presence of human anti-human antibodies (HAHAs). All patients tested negative at 24 weeks.
Overall, 72% (300 mg p<0.001; 700 mg p=0.001; 1000 mg p=0.001) of patients treated with each of the ofatumumab doses experienced at least a moderate (moderate or good) EULAR response compared to 40% of patients receiving placebo at week 24.
The data also showed that ofatumumab appeared well tolerated, with no increased frequency of serious infections. Approximately half of the adverse events occurred on infusion days (51%) with the most frequently reported being mild or moderate (CTC grade 1-2 events), including throat irritation, dyspnoea and rash.
Diffuse Large B-Cell Lymphoma
DLBCL is a cancer of the B-lymphocytes and represents 30% of non-Hogdkin's lymphomas in adults and is the most common lymphoid malignancy in the western world. There are an estimated 63,000 new cases of DLBCL diagnosed in the US per year. The median age at diagnosis is about 65 years.
Ongoing Clinical Studies
Phase III Head to Head Study
A Phase III study of ofatumumab in combination with chemotherapy versus rituximab plus chemotherapy in patients with relapsed or refractory DLBCL was initiated in November 2009. The study will include 380 patients who are refractory to or have relapsed following first line treatment with rituximab in combination with a chemotherapy regimen containing anthracycline and are eligible for autologous stemm cell transplant (ASCT). Patients in the study will be randomized to recieve three cycles of either ofatumumab or rituximab in addition to chemotherapy. After the third treatment cycle patients who obtain a complete or partial response will receive high dose chemotherapy followed by ASCT. The primary endpoint of the study is progression free survival.
Phase II Study
A Phase II study of ofatumumab to evaluate treatment of relapsed DLBCL in patients ineligible for or relapsed following a stem cell transplant was initiated in December 2007. Approximately 75 patients have been enrolled in the study. In the open label trial, each patient will receive 8 weekly infusions of ofatumumab. The first infusion will be 300 mg and the 7 subsequent infusions will be 1000 mg of ofatumumab. Disease status will be assessed 4 weeks after the last infusion and then every 3 months for a total of 24 months after treatment start according to the "Revised response criteria for malignant lymphoma." After 24 months, patients will be followed until initiation of alternative DLBCL treatment or month 60. The objective of the study is to determine the efficacy of ofatumumab in patients with relapsed DLBCL ineligible for transplant or relapsed after transplant. The primary endpoint of the study is objective response over a 6 month period from start of treatment.
Phase II Chemotherapy Combination Study
A Phase II study of ofatumumab in combination with ICE or DHAP chemotherapy in patients with relapsed or refractory DLBCL is ongoing. The study will include 48 patients with relapsed or refractory DLBCL following first line treatment with rituximab combined with an anthracycline-based regimen. Patients in this single-arm study will receive 3 cycles of ofatumumab (first dose 300 mg, 2 doses at 1000 mg) combined with salvage chemotherapy (either ICE or DHAP). Disease status will be monitored at each cycle. Response will be assessed by CT scan after cycle 2 and patients with progressive disease will not receive further treatment in the study. Patients who complete all 3 cycles will be assessed with PET and CT scans. Responses will be assessed according to the Cheson criteria. The objective of the study is to evaluate the overall response rate of ofatumumab in combination with ICE or DHAP chemotherapy prior to stem cell transplant. The primary endpoint is overall response rate.
Multiple Sclerosis (MS)
MS is an inflammatory disease of the central nervous system. MS is twice as common in females as in males, occurs with a peak incidence at the age of 35 years and incidence varies widely in different populations and ethnic groups. The etiology of MS remains unknown, but the geographic variation points towards possible environmental and genetic factors. The most common form of MS is relapsing remitting MS (RRMS) characterized by unpredictable recurrent attacks where the symptoms usually evolve over days and are followed by either complete, partial or no neurological recovery. No progression of neurological impairment is experienced between attacks.
Ongoing Clinical Studies
Phase II Study
In December 2007, Genmab announced details of a Phase II study of ofatumumab for the treatment of relapsing remitting multiple sclerosis. The first patient in the study was treated in June 2008. Approximately 324 patients will be enrolled in the study. The double blind randomized trial consists of two parts. Part A will include approximately 36 patients in one of three increasing dose cohorts (100 mg, 300 mg or 700 mg of ofatumumab) randomized to receive ofatumumab or placebo. An independent data monitoring committee (IDMC) will evaluate the safety of each sequential cohort prior to progression to the next cohort. When all patients in Part A have had their 4 week MRI scan, the IDMC will evaluate the data before Part B of the study begins.
Part B will consist of a 48 week treatment period of approximately 288 patients. Patients will be randomized to treatment with 100 mg, 300 mg or 700 mg of ofatumumab or placebo. After week 24, patients on an active dose will receive re-treatment with the same dose of ofatumumab or placebo. Patients on placebo will receive ofatumumab at the highest tolerated dose from Part A.
The objective of the study is to determine the safety and tolerability of three doses of ofatumumab and the dose response of ofatumumab on disease activity on MRI in patients with RRMS. The primary endpoints are safety and cumulative number of new Gd-enhanced lesions from week 8 to week 24.
Waldenstrom's Macroglobulinemia
Waldenstrom's Macroglobulinemia is a type of slow-growing non-Hodgkin's lymphoma.
Ongoing Clinical Studies
Phase II Study
A Phase II study of ofatumumab for the treatment of Waldenstrom's Macroglobulinemia is ongoing. A maximum of 36 patients will be included in the study. Patients will be divided into two groups with a minimum of 15 patients each based on whether they have received prior treatment. Patients in the open-label study will receive one dose of ofatumumab at 300 mg, followed by 3 weekly doses at 1000 mg. Patients in the prior treatment group that respond to ofatumumab but later relapse or progress while on the study may receive re-treatment. Disease status will be measured at week 12. Patients will be followed weekly through week 8, monthly through week 52 and then every 3 months until relapse or progression for up to 2 years. The objective of the study is to evaluate the overall response rate with ofatumumab for treatment of Waldenstrom's Macroglobulinemia. The primary endpoint is overall response rate.
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