• non-Hodgkin lymphoma;
  • oblimersen sodium;
  • rituximab;
  • recurrent B-cell NHL


  1. Top of page
  2. Summary
  3. Patients and methods
  4. Results
  5. Discussion
  6. Acknowledgement
  7. References

Oblimersen sodium plus rituximab was evaluated in relapsed/refractory B-cell non-Hodgkin lymphoma (NHL) patients. Oblimersen was administered as a continuous intravenous infusion at a daily dose of 3 mg/kg/d for 7 d on alternate weeks for 3 weeks. Rituximab was given at a weekly dose of 375 mg/m2 for six doses. Patients with stable disease or objective response were allowed to receive a second course of treatment. The overall response rate (ORR) was 42% with 10 complete responses (CR) and eight partial responses (PR). Twelve (28%) patients achieved a minimal response or stable disease. Among the 20 patients with follicular lymphoma the ORR was 60% (eight CR, four PR). Three of the responders were refractory to prior treatment with rituximab, and two of the responses occurred in patients who had failed an autologous stem cell transplant. Median duration of response was 12 months. Most toxicities were low grade and reversible. In conclusion, oblimersen sodium can be safely combined with rituximab. The combination appears to be most beneficial in patients with indolent NHL and warrants further investigation in a large randomized trial.

Bcl-2 is a potent inhibitor of apoptosis, and overexpression of this protein results in resistance to a variety of anti-cancer treatments (Reed, 1999). Overexpression of bcl-2 is common in non-Hodgkin lymphoma (NHL), and has been associated with poor clinical response and shorter survival (Hermine et al, 1996; Gascoyne et al, 1997).

Oblimersen sodium (Bcl-2 antisense oligonucleotide; G3139; Genasense; Genta incorporated, Berkeley Heights, NJ, USA) is a single-stranded 18 mer oligodeoxyribonucleotide, complimentary to the first six codons of the human bcl-2 reading frame. Studies of oblimersen on the BCL-2 overexpressing lymphoma cell lines DoHH2 and SU-DHL-4 in vitro have shown downregulation resultant in decrease in protein expression (Klasa et al, 2000). A number of in vitro studies have shown synergistic enhancement of tumour cell killing when Bcl-2 antisense was used to reduce Bcl-2 protein content in combination with standard anticancer therapy (Auer et al, 2001; Cotter et al, 2003). In a phase I study, oblimersen has been shown to modify Bcl-2 levels and induce objective responses in heavily pretreated patients with NHL (Waters et al, 2000).

Rituximab is an effective agent in the treatment of B-cell NHL, and many of the mechanisms of action of rituximab are potentially inhibited by Bcl-2. When antisense Bcl-2 oligonucleotides were used with murine aCD20 monoclonal antibody in severe combined immunodeficiency (SCID)/human lymphoma xenografts, a significant improvement in survival was observed (Smith et al, 2004).

Based on these data, we conducted a phase II study of oblimersen sodium and rituximab in patient with recurrent B-cell NHL to determine the efficacy and safety of this combination.

Patients and methods

  1. Top of page
  2. Summary
  3. Patients and methods
  4. Results
  5. Discussion
  6. Acknowledgement
  7. References


Patients with B-cell NHL were eligible if they had recurrent or refractory disease and had received at least one prior chemotherapy regimen that contained an anthracyclin or purine analog. Other inclusion criteria were age ≥18 years; Zubrod performance status ≤2; adequate organ function; no more than three prior chemotherapy regimens; and written informed consent. Exclusion criteria included active autoimmune disease; human immunodeficiency virus infection; pregnancy; prior exposure to oblimersen; hypersensitivity to phosphorothioaete-containing oligonucleotides; significant comorbidity; prior organ allograft; chronic lymphocytic leukaemia; history of second cancer; primary or metastatic central nervous system lymphoma, and active infection.

Institutional review boards at participating institutions approved the study. Written informed consent was obtained from all patients before undergoing study procedures. Women of childbearing potential were required to use adequate birth control methods.


Oblimersen sodium was administered as a continuous intravenous (IV) infusion via peripheral or central venous catheter using a portable infusion pump at a daily dose of 3 mg/kg/d for 7 d every other week (days 1–7, 15–21 and 29–35). Rituximab was given as IV infusion at a dose of 375 mg/m2 for six doses on days 3, 8, 15, 22, 29 and 36 (Fig 1). Patients with stable or responding disease were allowed to receive one additional course of therapy. Growth factors were administered at the investigator’s discretion.


Figure 1.  Treatment schema. CR, complete response; PR, partial response; SD, stable disease.

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Evaluation of response and toxicity

Baseline evaluation included physical examination, bone marrow aspirate and biopsy, and computed tomography of head and neck, chest, and abdomen and pelvis. Response was assessed after 8 weeks, 16 weeks and then every 3 months afterwards until progression. Response was evaluated according to the criteria of Cheson et al (1999). Safety was assessed weekly during treatment. Adverse events were graded according to the National Cancer Institute Common Toxicity Criteria (version 2.0;

Statistical methods

The primary end point was the overall response rate (ORR), which was defined as complete remission (CR) plus partial remission (PR). Separate assessment of efficacy was conducted in patients with low-grade lymphoma versus those with aggressive lymphoma. Patients receiving ≥1 week of treatment were evaluable for efficacy and all eligible patients were evaluable for toxicity.

A Bayesian monitoring method was used, with a prior distribution for the single agent rituximab treatment based on objective response rate observed in the previous trials.

Fisher’s exact tests were performed to assess the associations between two categorical variables. Wilcoxon rank sum test was used to evaluate the difference in age between the low grade and the aggressive lymphoma groups.

Progression-free survival (PFS) was defined as the time from enrolment to the date of progression disease or death. Overall survival (OS) was estimated as the time from the enrolment date to the date of death or last known alive. The Kaplan–Meier method was used to estimate survival distributions and the log-rank test (significance defined as P ≤ 0·05) was used to compare the survival distributions between patient groups, such as type of lymphoma, gender and age (median age was used as the cut-off point). All the statistical analyses were performed using SAS v9.2.0 (SAS Institute Inc., Cary, NC, USA) and SPLUS v7.0 (S-PLUS: Insightful Corporation, Seattle, WA, USA).


  1. Top of page
  2. Summary
  3. Patients and methods
  4. Results
  5. Discussion
  6. Acknowledgement
  7. References

A total of 48 patients were enrolled between January 2003 and October 2005, 42 were evaluable for response and 46 for toxicity. Baseline characteristics of the evaluable patients are listed in Table I. Six patients were not considered evaluable, one because of lack of measurable disease; one developed catheter-related deep vein thrombosis and was taken off study; three withdrew consent, and one was taken off study because of rapidly progressing disease after few days of treatment.

Table I.   Characteristics of evaluable patients.
CharacteristicNo of patients (n = 46)%
  1. SLL, small lymphocytic lymphoma; MALT, mucosa-associated lymphoid tissue lymphoma; DLBCL, diffuse large B-cell lymphoma; MCL, mantle cell lymphoma; NOS, not otherwise specified.

Age (years)
Prior regimen
 Range 1–3 
 Prior rituximab3268
 Follicular G1-21532
 Follicular G-3511
 Low-grade NOS12

The median number of prior treatments was 2 (range 1–3) and 70% of patients had received prior treatment with rituximab either alone or in combination with chemotherapy.

Patients were defined to be rituximab-refractory if they did not respond to previous rituximab treatment or if the time to progression after previous rituximab treatment was less than 6 months. Fourteen (30%) patients were refractory to prior treatment with rituximab. Twenty-one patients (50%) received two courses of treatment, and 21 (50%) one course.


There were 10 CR (23%) and eight PR (19%) among the 42 assessable patients, for an overall response rate of 42%. Also, 12 patients (28%) achieved a minimal response or stable disease. Response by histology is shown in Table II. The majority of responses occurred in patients with follicular lymphoma. Among the 20 patients with follicular lymphoma, eight (40%) achieved a CR and four (20%) a PR, to give an ORR of 60%. Seven of the responding patients had never received prior rituximab. However, among these seven patients, two had failed an autologous transplant, including one with large cell histology. Three responses (two CR, one PR) were observed in the 14 patients (21%) refractory to prior treatment with rituximab. Among patients with CR/PR all responses were durable, including the subgroup with rituximab-refractory disease, with five responses still ongoing at 20–48 months. Two responders underwent successful autologous stem cell transplantation. Characteristics of all responders are shown in Table III. The median duration of response was 12 months. Kaplan–Meier estimates for OS and PFS are shown in (Fig 2). No statistically significant difference in OS for aggressive versus low-grade subtypes was detected. The difference in PFS between the two groups of lymphoma was marginally significant (P-value = 0·066; Hazard ratio 0·268; 95% Confidence interval 0·063–1·142) (Fig 3).

Table II.   Response stratified by histology.
Histology, nEvaluable patients (= 42)
  1. CR, complete response; PR, partial response; SD, stable disease; PD, progressive disease; ORR, overall response rate; SLL, small lymphocytic lymphoma; DLCL, diffuse large-cell lymphoma.

  2. One patient with B-cell lymphoma low-grade NOS achieved stable disease.

Follicular (= 20)844460
Mantle-cell (= 5)012220
SLL (= 6)110133
Marginal-zone (= 3)110166
DLCL (= 7)022328
Table III.   Characteristics of the 18 patients with responsive disease.
PatientHistologyPrior therapiesResponseTTP (months)Exposure/response to previous rituximab
  1. TTP, time to progression; FL, follicular lymphoma; MALT, mucosa-associated lymphoid tissue lymphoma; SLL, small lymphocytic lymphoma; MZL, marginal zone lymphoma; MCL, mantle cell lymphoma; LCL, large cell lymphoma; CR, complete response; PR, partial response; Y, yes; N, no; NA, not applicable; Auto, autologous bone marrow transplantation.

  2. *Patients underwent autologous transplant after one course of therapy.

  3. †Patient lost to follow-up.


Figure 2.  Kaplan–Meier curves of (A) overall survival for and (B) progression-free survival (PFS) for all evaluable patients (n = 42).

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Figure 3.  Kaplan–Meier curve of progression-free survival for all evaluable patients according to histological subtype (n = 42).

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Overall, the combination was well tolerated and myelosuppression was the main haematological toxicity in this study. The most common adverse events are listed in Table IV. None of the patients experienced a cytokine release reaction. Although grade 3 and 4 neutropenia was observed in 15% of patients, patients responded well to granulocyte colony-stimulating factor. None of the patients experienced a severe infection. Reversible thrombocytopenia was observed in 21% of patients, only 4% grade ≥3. As reported in earlier studies, the most common non-haematological toxicity was fatigue.

Table IV.   Toxicity (= 46).
Toxicity, no. of patientsGrade 1Grade 2Grade 3/4Total (%)
Anaemia185124 (52)
Thrombocytopenia44210 (21)
Neutropenia21710 (21)
Fatigue710320 (43)
Oedema9 110 (21)
Rash45 9 (19)
Fever3216 (13)


  1. Top of page
  2. Summary
  3. Patients and methods
  4. Results
  5. Discussion
  6. Acknowledgement
  7. References

Herein, we describe the first experience of oblimersen combined with rituximab in the treatment of B-cell NHL. This study demonstrated that oblimersen can be administered safely with rituximab in patients with previously treated B-cell NHL. The initial clinical trial of oblimersen was conducted in 21 patients with NHL at doses ranging from 0·125 to 5·3 mg/kg/d. Thrombocytopenia, infusion reaction, and fatigue were felt to be dose-limiting in two patients treated at a level of 5·3 mg/kg/d. (5) Several earlier phase I trials have shown that the maximum-tolerated dose (MTD) varied according to the duration of infusion and types of malignancies. Patients with haematological malignancies appear to be more sensitive to the drug, and in the initial trial of oblimersen in patients with NHL the MTD was determined to be 4 mg/kg/d, approximately one-half that of patients with solid tumours. The 3 mg/kg/dose level, given IV continuous infusion for 7 d, was well tolerated in our patient population and we did not observe the cytokine release reaction previously reported in patients with chronic lymphocytic leukaemia (O’Brien et al, 2005, 2007). Thrombocytopenia was observed in 21% of patients; all patients recovered to normal by the time of the next infusion, and no case of thrombocytopenia was associated with bleeding. Similarly, neutropenia was observed in 21% of patients and was completely reversible.

This paper also provides the first report of the therapeutic efficacy of oblimersen in various histologies of B-cell NHL. Although recent reports suggest that oblimersen may add to the activity of R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone) in previously untreated mantle cell lymphoma (MCL) (Leonard et al, 2003a,b), our study demonstrated a modest activity in patients with recurrent disease.

Similarly, limited efficacy was observed in patients with recurrent diffuse large B-cell lymphoma (DLBCL). The lack of efficacy demonstrated by this study in patients with aggressive histologies is probably multifactorial. The clinical course and prognosis of patients with diffuse large cell lymphoma (DLCL) and MCL who have failed a median of two prior treatments is significantly worse than patients with low-grade histologies. Also, multiagent chemotherapy regimens with or without monoclonal antibodies are in general more effective treatments in aggressive histologies when compared with single chemotherapy agents or immunotherapy alone.

In this study, the highest response rate was observed in patients with follicular lymphoma. In an earlier study (Davis et al, 2000), re-treatment with rituximab produced responses in approximately 40% of patients with low-grade NHL who previously responded to it. In the current study, 70% of patients with follicular lymphoma had received prior treatment with rituximab. An encouraging objective rate of 60% was observed, confirming a suggestion from earlier preclinical data of a synergy between oblimersen and rituximab.

Notably, the combination of rituximab and oblimersen sodium was effective in patients with rituximab-refractory disease, suggesting that oblimersen could overcome mechanisms of rituximab-resistance.

In conclusion, the combination of oblimersen and rituximab, appears to be promising in the subgroup of patients with indolent NHL and warrants further investigation in a large randomized trial. Additionally, given the good safety profile, further evaluation of its activity in combination with cytotoxic agents is warranted.


  1. Top of page
  2. Summary
  3. Patients and methods
  4. Results
  5. Discussion
  6. Acknowledgement
  7. References

This study was supported by the National Cancer Institute Grant No 01/CM17003.


  1. Top of page
  2. Summary
  3. Patients and methods
  4. Results
  5. Discussion
  6. Acknowledgement
  7. References
  • Auer, R.L., Corbo, M., Fegan, C.D., Frankel, S.R. & Cotter, F.E. (2001) Bcl-2 antisense (Genasense) induces apoptosis and potentiates activity of both cytotoxic chemotherapy and rituximab in primary CLL cells. Blood, 98, 808a.
  • Cheson, B.D., Horning, S.J., Coiffier, B., Shipp, M.A., Fisher, R.I., Connors, J.M., Lister, T.A., Vose, J., Grillo-Lopez, A., Hagenbeek, A., Cabanillas, F., Klippensten, D., Hiddemann, W., Castellino, R., Harris, N.L., Armitage, J.O., Carter, W., Hoppe, R. & Canellos, G.P. (1999) Report of an international workshop to standardize response criteria for non-Hodgkin’s lymphomas. NCI Sponsored International Working Group. Journal of Clinical Oncology, 17, 1244.
  • Cotter, F.E., Auer, R., Corbo, M., McElwaine, S. & Frankel, S.R. (2003) Oblimersen sodium (G3139) sensitizes malignant B-cells to alemtuzumab induced apoptosis. Journal of Clinical Oncology, 22, 227a.
  • Davis, T.A., Grillo-Lopez, A.J., White, C.A., McLaughlin, P., Czuczman, M.S., Link, B.K., Maloney, D.G., Weaver, R.L., Rosenberg, J. & Levy, R. (2000) Rituximab anti-CD20 monoclonal antibody therapy in non-Hodgkin’s lymphoma: safety and efficacy of re-treatment. Journal of Clinical Oncology, 18, 31353143.
  • Gascoyne, R.D., Adomat, S.A., Krajewski, S., Krajewska, M., Horsman, D.E., Tolcher, A.W., O’Reilly, S.E., Hoskins, P., Coldman, A.J., Reed, J.C. & Connors, J.M. (1997) Prognostic significance of Bcl-2 protein expression and Bcl-2 gene rearrangement in diffuse aggressive non-Hodgkin’s lymphoma. Blood, 90, 244251.
  • Hermine, O., Haioun, C., Lepage, E., D’Agay, M.F., Briere, J., Lavignac, C., Fillet, G., Salles, G., Marolleau, J.P., Diebold, J., Reyas, F. & Gaulard, P. (1996) Prognostic significance of bcl-2 protein expression in aggressive non-Hodgkin’s lymphoma. Groupe d’Etude des Lymphomes de l’Adulte (GELA). Blood, 87, 265272.
  • Klasa, R.J., Bally, M.B., Ng, R., Goldie, J.H., Gascoyne, R.D. & Wong, F.M. (2000) Eradication of human non-Hodgkin’s lymphoma in SCID mice by BCL-2 antisense oligonucleotides combined with low-dose cyclophosphamide. Clinical Cancer Research, 6, 24922500.
  • Leonard, J.P., Coleman, M., Vose, J., Hainsworth, J.D., Piro, L., Saleh, M., Berstein, S., Ferero-Torres, A., Frankel, S.R. & Itri, L.M. (2003a) Phase II study of oblimersen sodium (G3139) alone and with R-CHOP in mantle cell lymphoma (MCL). Proceedings of American Society of Clinical Oncology, 22, 566.
  • Leonard, J.P., Hainsworth, J., Bernstein, S., Ferero-Torres, A., Vose, J., Piro, L., Saleh, M., Coleman, M., Frankel, S., Smith, S. & Itri, L. (2003b) Genasense (oblimersen sodium, G3139) is active and well tolerated both alone and with R-CHOP in mantle cell lymphoma (MCL). Blood, 102, 143a.
  • O’Brien, S.M., Cunningham, C.C., Golenkov, A.K., Turkina, A.G., Novick, S.C. & Rai, K.R. (2005) Phase I to II multicenter study of oblimersen sodium, a Bcl-2 antisense oligonucleotide, in patients with advanced chronic lymphocytic leukemia. Journal of Clinical Oncology, 23, 76977702.
  • O’Brien, S., Moore, J.O., Boyd, T.E., Larratt, L.M., Skotnicki, A., Koziner, B., Chanan-Khan, A.A., Seymour, J.F., Bociek, R.G., Pavletic, S. & Rai, K.R. (2007) Randomized phase III trial of fludarabine plus cyclophosphamide with or without oblimersen sodium (Bcl-2 antisense) in patients with relapsed or refractory chronic lymphocytic leukemia. Journal of Clinical Oncology, 25, 11141120.
  • Reed, J.C. (1999) Dysregulation of apoptosis in cancer. Journal of Clinical Oncology, 17, 29412953.
  • Smith, M.R., Jin, F. & Joshi, I. (2004) Enhanced efficacy of therapy with antisense BCL-2 oligonucleotides plus anti-CD20 monoclonal antibody in scid mouse/human lymphoma xenografts. Molecular Cancer Therapeutics, 3, 16931699.
  • Waters, J.S., Webb, A., Cunningham, D., Clarke, P.A., Raynaud, F., Di Stefano, F. & Cotter, F.E. (2000) Phase I clinical and pharmacokinetic study of bcl-2 antisense oligonucleotide therapy in patients with non-Hodgkin’s lymphoma. Journal of Clinical Oncology, 18, 18121823.