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Clinical Cancer Research 13, 6168, October 15, 2007. doi: 10.1158/1078-0432.CCR-07-0815
© 2007 American Association for Cancer Research
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Cancer Therapy: Clinical

Phase I Trial of Toll-Like Receptor 9 Agonist PF-3512676 with and Following Rituximab in Patients with Recurrent Indolent and Aggressive Non–Hodgkin's Lymphoma

John P. Leonard1, Brian K. Link2, Christos Emmanouilides3, Stephanie A. Gregory4, Daniel Weisdorf5, Jeffrey Andrey6, John Hainsworth7, Joseph A. Sparano8, Donald E. Tsai9, Sandra Horning10, Arthur M. Krieg11 and George J. Weiner2

Authors' Affiliations: 1 Weill Medical College of Cornell University and New York Presbyterian Hospital, New York, New York; 2 University of Iowa, Iowa City, Iowa; 3 University of California at Los Angeles Medical Center, Los Angeles, California; 4 Rush-Presbyterian-St. Luke's Medical Center, Chicago, Illinois; 5 University of Minnesota, Minneapolis, Minnesota; 6 Scripps Clinic, La Jolla, California; 7 Sarah Cannon Cancer Center, Nashville, Tennessee; 8 Montefiore-Einstein Cancer Center, Albert Einstein College of Medicine, Bronx, New York; 9 University of Pennsylvania Medical Center, Philadelphia, Pennsylvania; 10 Stanford University Medical Center, Palo Alto, California; and 11 Coley Pharmaceutical Group, Inc., Wellesley, Massachusetts

Requests for reprints: George J. Weiner, Holden Comprehensive Cancer Center at the University of Iowa, 5970Z JPP, 200 Hawkins Drive, University of Iowa, Iowa City, IA 52242. Phone: 319-353-8620; Fax: 319-353-8988; E-mail: george-weiner{at}uiowa.edu.


   Abstract
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 Abstract
Materials and Methods
 Results
 Discussion
 References
 
Purpose: PF-3512676 (formerly CpG 7909) is a novel Toll-like receptor 9–activating oligonucleotide with single-agent antitumor activity that augments preclinical rituximab efficacy. This Phase I trial was designed to investigate the safety, tolerability, and preliminary antitumor activity of PF-3512676 in combination with rituximab.

Experimental Design: Patients with relapsed/refractory CD20+ B cell non–Hodgkin's lymphoma received i.v. rituximab (375 mg/m2/week for 4 weeks) and PF-3512676 weekly for 4 weeks either i.v. (0.04, 0.16, 0.32, or 0.48 mg/kg) or s.c. (0.01, 0.04, 0.08, or 0.16 mg/kg). An additional extended-treatment cohort received 4 weeks of 0.24 mg/kg s.c. PF-3512676 in combination with rituximab followed by s.c. PF-3512676 alone weekly for 20 weeks.

Results: Patients (N = 50) had received a median of three prior therapies (range, 1-11) including rituximab in 80% of patients. Treatment-related adverse events occurred in 11 of 19 (58%) i.v. patients, 15 of 19 (79%) s.c. patients, and all 12 patients in the extended-treatment cohort. Most common adverse events were mild to moderate systemic flu-like symptoms and injection-site reactions (s.c. cohorts only). Grade 3/4 neutropenia occurred in four patients. Objective responses occurred in 12 of 50 (24%) patients overall and in 6 of 12 (50%) patients in the extended-treatment cohort, including 2 patients with rituximab-refractory disease.

Conclusion: Brief or extended-duration PF-3512676 can be safely administered in combination with rituximab in patients with relapsed/refractory non–Hodgkin's lymphoma.

Toll-like receptors (TLR) detect molecular structures common to infectious pathogens and can induce an immune response (1). For example, TLR9 is stimulated by oligodeoxynucleotides containing unmethylated CpG dinucleotides (CpG ODN) that resemble sequences commonly are found in bacterial and viral DNA. These sequences are underrepresented and predominantly methylated in vertebral DNA (2). In humans, the normal expression of TLR9 is primarily restricted to plasmacytoid dendritic cells and B cells (3–5). TLR agonists are a novel approach to anticancer therapy; they activate dendritic cells and can stimulate more effective antitumor immunity. In animal models, TLR9-activating oligodeoxynucleotides containing one or more CpG motifs have shown antitumor activity (2).

CpG ODN have a variety of effects on B cells that may be relevant in the treatment of B cell malignancies. Most of these effects seem to be due to interaction with TLR9. Activation of normal B cells through TLR9 causes them to produce higher levels of proinflammatory cytokines and costimulatory molecules and to show decreased spontaneous apoptosis (2). TLR9 activation of primary malignant B cells, including those involved in non–Hodgkin's lymphoma (NHL) and chronic lymphocytic leukemia (CLL), up-regulates expression of MHC class I and class II molecules, CD20, CD40, CD80, and CD86 (6–8) and induces apoptosis in CLL cells (9). CpG ODN–stimulated malignant B cells are more effective than unstimulated cells at activating T cells in allogeneic mixed lymphocyte cultures, suggesting the possibility of inducing an antitumor T cell response. CpG ODN–treated CLL cells are also sensitized to other immunotherapies without enhancing toxicity to normal cells (10). In particular, up-regulation of CD20 may sensitize malignant B cells to the cytotoxic effects of rituximab (anti-CD20).

CpG ODN activation of plasmacytoid dendritic cells causes increased expression of costimulatory molecules and secretion of type I IFN and chemokines; activation of immune effector cells including monocytes, natural killer (NK) cells, NKT cells, and neutrophils; and enhanced induction of adaptive, antigen-specific cytotoxic T cell responses.

In a murine lymphoma model, treatment with CpG ODN enhanced cytotoxicity of an antitumor monoclonal antibody (MAb; ref. 11), suggesting that the combination of CpG ODN with an MAb may be effective in human cancer. Together, these effects of CpG ODN activation result in both direct and indirect antitumor activities.

Rituximab (Rituxan) is a MAb directed against human CD20 (12), which is expressed on normal pre-B and mature B cells and on malignant B cells in 95% of patients with B cell NHL (13, 14). Rituximab has been shown to be effective when given as monotherapy (15) or when combined with chemotherapy (16). Unfortunately, the effects of treatment can be limited; some patients have either a short-term response or do not respond at all (17, 18). PF-3512676 is a TLR9-activating CpG oligonucleotide that has shown antitumor effects both in animal models and in human clinical trials (19–23). The single-agent activity of PF-3512676 has been observed in human clinical trials in NHL, melanoma (24), renal cell carcinoma (25), cutaneous T cell lymphoma (26), and basal cell carcinoma (27). Because TLR9 agonists such as PF-3512676 induce the up-regulation of costimulatory markers and CD20 expression on malignant B cells, one consideration for combination therapy would be that the infusion-related toxicity and/or antitumor activity of rituximab might be potentiated by concurrent treatment with PF-3512676 (7, 28).

The goal of this open-label, phase I study was to investigate the safety, tolerability, and preliminary antitumor activity of brief or extended duration therapy with PF-3512676 in combination with rituximab (375 mg/m2) in patients with relapsed or refractory B cell NHL. Herein, we report the final analysis of this trial.


   Materials and Methods
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 Abstract
 Materials and Methods
Results
 Discussion
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Study population
Patients with histologically confirmed relapsed or refractory CD20+ NHL were enrolled, including patients who had received prior MAb treatment, provided that such therapy had last been administered at least 90 days before enrollment (or at least 30 days prior if refractory). Eligibility criteria included measurable disease; no central nervous system involvement; age ≥18 years; Eastern Cooperative Oncology Group (ECOG) performance status ≤2; life expectancy >3 months; no serologic evidence of hepatitis virus B or C or HIV; no history of allergic reactions to rituximab, PF-3512676, or similar agents; no other significant preexisting medical conditions such as cardiovascular or pulmonary disease; and adequate hematologic and organ function determined as absolute neutrophil count ≥1,000/µL, platelets ≥50,000/µL, serum creatinine <2 mg/dL, bilirubin <2 mg/dL, and transaminase activity less than twice the upper limit of normal. Patients were excluded from the study if they had a history of allogeneic transplants or autoimmune or antibody-mediated diseases (e.g., systemic lupus erythematosus, Sjögren's syndrome). Confounding therapies (e.g., cytotoxic chemotherapy, immunosuppressants, corticosteroids, or hematopoietic growth factors) within 30 days were not allowed.

This study was done according to Good Clinical Practice guidelines of the International Council on Harmonization and followed the principles of the Declaration of Helsinki. The protocol and informed consent forms were reviewed and approved by the institutional review boards of each participating institution before study initiation. All patients provided signed informed consent.

Study design
This was a multicenter, open-label, phase I trial with two treatment arms (i.v. or s.c.) designed to assess the safety and preliminary antitumor activity of PF-3512676 in combination with rituximab. The primary objective for this study was to determine the safety and tolerability of repeated dose levels of s.c. and i.v. CpG 7909 in patients receiving rituximab for relapsed or refractory B cell NHL. The secondary objective was to evaluate the overall tumor response rate at day 50 ± 3 days in all cohorts and at completion of therapy in an extended dosing cohort. All patients received four weekly i.v. infusions of standard-dose rituximab (375 mg/m2), each followed within 24 h by either a 2-h i.v. infusion or an s.c. injection of PF-3512676, a 24-mer tricosasodium salt phosphorothioate ODN (sequence 5'-TCGTCGTTTTGTCGTTTTGTCGTT-3') supplied by the Coley Pharmaceutical Group (Wellesly, MA).

The doses of PF-3512676 were assigned to sequential cohorts with three patients per cohort. Cohorts were expanded to ≥6 patients if a single patient experienced dose-limiting toxicity (DLT), and escalation to the next dosing cohort continued if no more than one DLT was observed in the cohort. The maximum tolerated dose (MTD) would be considered exceeded if more than one DLT was observed in any cohort before reaching the target dose (defined as the highest of the four dose levels within each route of administration). Four dose levels were evaluated for each route of administration: i.v. cohorts received 0.04, 0.16, 0.32, or 0.48 mg/kg, and s.c. cohorts received 0.01, 0.04, 0.08, or 0.16 mg/kg. The target dose of 0.32 mg/kg for i.v. cohorts was determined based on data establishing NK cell activity at that level in a prior single-agent phase I study in previously treated NHL patients (21) and target level of 0.24 mg/kg in s.c. cohort based on tolerance studies in normal volunteers (29). Criteria for DLTs included any nonhematologic grade 4 adverse event (AE), any hematologic grade 4 AE (excluding anemia) with a duration of >7 days or febrile neutropenia, and any grade 3 AE (excluding lymphopenia, flu-like symptoms, nausea, or vomiting) >2 weeks in duration. The study was expanded to include a third cohort of extended s.c. dosing after preliminary findings suggested that low doses of PF-3512676 with rituximab were well tolerated. This cohort evaluated a higher dose of PF-3512676 (0.24 mg/kg) administered via an s.c. injection in combination with rituximab for 4 weeks and then as monotherapy for an additional 20 weeks.

Clinical assessments
Safety assessment. At screening, patients were questioned about medical and treatment history, including specific therapies for NHL and preexisting symptoms. Serum samples were analyzed for antinuclear antibody, rheumatoid factor, anti–double-stranded DNA, antithyroid, and human antimouse antibodies, but patients were not excluded from enrollment on the basis of these results. At screening, on each day of treatment, and 6 to 8 days after the last treatment, patients were examined, vital signs were recorded, ECOG performance status was assessed, and blood samples were taken for routine hematology. In addition, a urinalysis for all patients and urine pregnancy test for all women of childbearing age were done. On the first day of treatment, coagulation was evaluated first by measurement of prothrombin times and activated partial thromboplastin times (aPTT) before rituximab infusion and then by aPTT immediately before (i.v. arm only) and 1 h after (i.v. and s.c. arms) PF-3512676 infusion. Additional assessments included routine hematology at 3 to 5 days and serum chemistries and urinalyses at 2 weeks from the start of treatment. Except for assessment of coagulation, all safety evaluations done at screening were repeated at the end of the study (~4 weeks after the last treatment) or at the time of patient withdrawal.

Patients in the extended s.c. dosing cohort had similar evaluations during the 4 weeks of combined therapy. During the 20 weeks of PF-3512676 monotherapy, these patients continued with weekly injections and concurrent assessments of ECOG performance status, vital signs, and routine hematology. Serum chemistries and urinalyses were done on the first day of monotherapy and every 4 weeks thereafter until the end of study. Final safety assessment was done as above.

Adverse events were recorded at each visit, categorized for association with study treatment (unrelated, unlikely, possibly, probably, or definitely), and graded according to the National Cancer Institute Common Toxicity Criteria (CTC) version 2.0.

Disease assessment. The extent of disease was assessed at screening and following end of treatment by measurement of lesions on radiographs, computed axial tomography, or magnetic resonance imaging. Response to therapy was classified according to the International Workshop for NHL response criteria (30). The overall tumor response rate was based on the number of patients whose best response during the study was complete response, complete response unconfirmed, or partial response. Duration of response or extended evaluation for delayed or improved response beyond the official study period was not assessed in this phase I trial.

Statistical considerations
Sample size for each cohort was determined by frequency of DLTs. The dose escalation scheme, described previously, ensured that no more than 16.7% of patients (one of six) experienced DLT at the target doses. A total of 12 evaluable patients were subsequently enrolled to the extended s.c. dosing cohort so that margins of error associated with 90% confidence intervals for tumor response would not exceed 25%. Descriptive statistics were used to summarize the study patients. Toxicity was graded by Common Terminology Criteria for Adverse Events Version 3.0, and tumor response was defined by National Cancer Institute lymphoma workshop consensus response criteria (30). Distinct patient populations were used for analysis of efficacy and safety. The safety population was comprised of all patients who received treatment on day 1. The intent-to-treat (ITT) population consisted of those patients enrolled into the study who received at least one dose of CpG 7909. The ITT population was used for all efficacy analyses. All statistical analyses were done using the SAS software program.


   Results
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 Abstract
 Materials and Methods
 Results
Discussion
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Patient characteristics
Demographic characteristics for patients enrolled in the i.v. and s.c. arms are presented in Tables 1 and 2 . Patients had either indolent or aggressive lymphoma (~50% each), and all but one had been previously treated with chemotherapy. Most subjects had received prior anti-CD20 therapy, including 18 of 19 with follicular histology. The small number of patients in each treatment cohort limits comparisons of different subgroups with respect to baseline characteristics.


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  		Table 1. Characteristics of patients enrolled in the i.v. arm

 

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  		Table 2. Characteristics of patients enrolled in the s.c. arm

 
Safety
Across all groups, 38 of 50 (76%) patients had ≥1 treatment-related AE. Overall, fewer patients in 4-week i.v. cohorts [11 of 19 (58%) patients] had treatment-related AEs than did patients in 4-week s.c. cohorts [15 of 19 (79%) patients], although differences were not statistically significant. All 12 patients (100%) in the extended s.c. dosing cohort had treatment-related AEs. Increased and extended dosing with PF-3512676 was associated with mild to moderate flu-like symptoms. However, there were no other consistent trends in AEs; grade 3/4 AEs rarely occurred in more than one patient or at >1 dose level. No tumor flare reactions were observed.

Treatment-emergent AEs in patients in the 4-week i.v. arm. Among patients in the i.v. arm, treatment-related AEs were manageable, and there were no grade 4 AEs. The most common AEs were mild to moderate systemic flu-like symptoms (e.g., fever, fatigue, headache). Although no AEs developed in the low-dose group (0.04 mg/kg), there was no clear relationship between the dose of PF-3512676 and the incidence or severity of the treatment-related AEs at higher doses. One patient in the 0.16-mg/kg dose group had a serious AE (Table 3 ); this patient developed severe (grade 3) vomiting and diarrhea 11 days after receiving the last infusions of rituximab and PF-3512676. The patient recovered but later developed renal vein thrombosis deemed unrelated to study drug and withdrew from the study. Treatment was also discontinued in one patient (0.32 mg/kg cohort) who experienced a reaction (flushing and pain in the back, limb, and abdomen) during the second rituximab infusion.


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  		Table 3. Patients in the i.v. arm with grade 3/4 treatment-emergent adverse events

 
Hematologic AEs occurred in one patient in each of the 0.32- and 0.48-mg/kg i.v. dose groups (Table 3). The patient treated with 0.32 mg/kg PF-3512676 developed grade 3 leukopenia and lymphopenia 3 days after the first treatment, which persisted through the end of the study (~80 days), and grade 3 neutropenia lasting ~11 days. The patient treated with 0.48 mg/kg PF-3512676 developed grade 3 neutropenia lasting for 9 days.

Treatment-emergent AEs in patients in the 4-week s.c. arm. The spectrum of observed AEs in the s.c. arm was similar to that observed in the i.v. arm with the addition of injection-site reactions. The most frequent AEs were mild or moderate systemic flu-like symptoms (e.g., fatigue, pyrexia, headache, malaise) and injection-site reactions. A dose-dependent trend was seen in the incidence of systemic flu-like symptoms and injection-site reactions. Flu-like illness, fatigue, and pyrexia were observed more frequently in the highest dose cohort (0.16 mg/kg). In addition, one of three (33%) patients in the low-dose group (0.01 mg/kg) had mild erythema at the injection site, and three of six (50%) patients in the high-dose group (0.16 mg/kg) had mild to moderate erythematous injection-site reactions.

As in the i.v. arm, hematologic AEs occurred; one patient in the s.c. arm (0.08-mg/kg dose group) developed moderate to severe hematologic changes (Table 4 ). Grade 4 neutropenia lasted ~1 week, after which the neutropenia improved to grade 3 but persisted. Although the patient had no fever or sequelae from the persistent neutropenia, this finding was considered a possible dose-limiting toxicity, and the number of patients in the cohort was increased to seven. No patients in the s.c. cohorts developed serious AEs related to the study drug. All patients completed 4 weeks of treatment, but two patients (one each treated at 0.01 and 0.08 mg/kg) withdrew from the study 1 to 2 weeks after completing the last injection because of progressive disease. No grade 3 or 4 autoimmune events were noted.


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  		Table 4. Patients in the s.c. arm with grade 3/4 treatment-emergent adverse events

 
Treatment-emergent AEs in patients with extended s.c. therapy. Patients treated with the highest dose of PF-3512676 (0.24 mg/kg) administered via s.c. injection in combination with rituximab and then as monotherapy had more frequent AEs similar in type to those seen in other patients treated with s.c. PF-3512676. The most common AEs among the 12 patients in this cohort were mild to moderate (grade 1/2) injection-site reactions or systemic symptoms (e.g., fatigue or rigors, pyrexia, flu-like illness, and malaise). Injection-site reactions, including local erythema, pain, edema, pruritus, bruising, and indurations, were reported in 8 of 12 (67%) patients. A hematologic AE was reported by one patient in this cohort (grade 3 neutropenia), and grade 3 pain in limbs was reported by two (17%) patients (Table 4).

In this cohort, all 12 patients received the initial 4 weeks of combination rituximab and PF-3512676 treatment, and 7 patients completed the extended PF-3512676 dosing. Five patients were withdrawn before completing extended dosing (two because of disease progression and three because of treatment-related AEs). Among the three patients who withdrew due to treatment-related AEs, one requested to withdraw because of grade 1/2 flu-like symptoms, injection site reactions, and generalized pruritus; one developed a peripheral neuropathy (plantar pain); and the third developed a Sjögren's-like syndrome, which was the only serious AE observed in the s.c. arm. This patient reported both conjunctivitis and oral mucositis. Histologic examination of a minor salivary gland showed atrophy, fibrosis, and a T cell infiltrate predominantly composed of CD8 T cells, which was reported as a Sjögren's-like syndrome. PF-3512676 therapy was discontinued, and low-dose corticosteroid therapy was initiated, which led to the improvement of both the oral and conjunctival symptoms.

Antitumor activity
In this heterogenous group of patients with NHL, 12 of 50 (24%) patients had a complete or partial response (Table 5 ). Among patients enrolled in the 4-week dosing cohorts, 4 of 19 (21%) in the i.v. arm and 2 of 19 (10.5%) in the s.c. arm had a complete or partial response, and there were 11 (57.9%) and 10 (52.6%) patients, respectively, with stable disease as best response. No dose-response relationship was apparent in either group. A total of 6 of 12 (50%) patients in the extended s.c. dosing cohort had a complete or partial response, and there were three (25%) patients with stable disease. Five of the six responding patients in this cohort met criteria for response at the day 50 evaluation. Overall, when patients were assessed according to indolent or aggressive histology, the objective response rate was similar in both subgroups (24%; Table 6 ). A total of 7 of 19 patients with follicular lymphoma entered the study with a history of rituximab-refractory disease (no response or response <6 months to previous rituximab), and two of these subjects responded to rituximab plus PF-3512676 (one partial response in the 0.16-mg/kg s.c. cohort and one complete response in the extending s.c. dosing cohort). Twelve FL patients across all cohorts were not rituximab resistant. Eleven had received one prior course of ant-CD20 therapy, and one was anti-CD20 naive. Two of those twelve FL patients responded to rituximab plus PF-3512676.


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  		Table 5. Overall tumor response

 

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  		Table 6. Tumor responses by histologic subtype

 

   Discussion
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 Abstract
 Materials and Methods
 Results
 Discussion
References
 
This trial shows that in patients with relapsed or refractory NHL, PF-3512676 can be safely combined with rituximab across a range of doses and with three different dosing strategies. Both i.v. and s.c. routes of administration were included in this study. Intravenous dosing is of interest because in mice, i.v. injections of PF-3512676 led to a redistribution of dendritic cells in the spleen (31, 32), and in previously treated lymphoma patients, i.v. injections resulted in increased NK cell number and activity and was generally well tolerated without significant change in serum cytokines (21). Subcutaneous administration was of interest because s.c. injections elicited a dose-dependent increase in serum cytokines and chemokines in healthy human volunteers (29). Furthermore, s.c. administration of a similar CpG ODN (1018 ISIS), combined with rituximab in lymphoma patients, has been shown to induce Th1 cytokines and chemokines (33). These findings suggested that the route of administration might affect the tolerability and/or antitumor activity of PF-3512676.

The most common AEs were mild to moderate systemic flu-like symptoms and, in patients receiving s.c. injections of PF-3512676, mild to moderate injection-site reactions. Treatment-related hematologic changes were infrequent and mostly mild to moderate in severity. Four patients developed severe neutropenia, which lasted 8 to 11 days in three patients and was prolonged in the fourth patient, without evidence of neutropenic infection. Peripheral neutropenia may reflect a transient redistribution of neutrophils out of the peripheral blood without myelosuppression. Neutropenia to a similar degree was seen in the phase I study of i.v. PF-3512676 in NHL patients and is not commented on in the report of s.c. 1018 ISIS in combination with rituximab (33). It was anticipated that infusion reactions associated with rituximab might be increased with the addition of PF-351676 because in vitro studies show that this agent can up-regulate the expression of CD20 by lymphoma cells, and CpG ODN itself can enhance production of a variety of cytokines that might contribute to such reactions. However, such reactions were seen at the rate and intensity that would be expected with rituximab alone, with only one patient withdrawing due to rituximab intolerance. Treatment-related AEs were more common in the patients receiving extended s.c. dosing at 0.24 mg/kg, leading to 25% discontinuation of therapy.

One patient with CLL/small lymphocytic lymphoma/PLL and normal baseline DS DNA titers developed Sjögren's-like inflammation of the salivary gland and keratoconjunctivitis sicca during the study. Induction of such autoimmune reactions is a potential toxicity that needs to be monitored closely when using immunostimulatory agents therapeutically. A causal relationship in this instance is possible but speculative. Sjögren's syndrome has not been reported in previous studies of PF-3512676. Additionally, paraneoplastic autoimmune diseases can develop spontaneously in patients with B cell neoplasms (34, 35). Recent retrospective epidemiologic studies have shown an association between NHL and several autoimmune diseases, of which Sjögren's syndrome is the most common (36).

The 24% objective response rate observed with this combination regimen in the overall patient population was lower than that previously reported in indolent NHL patients who were treated with single-agent rituximab (15, 37). In contrast to these earlier studies, our trial included patients with aggressive histologies, rituximab-refractory disease, and subjects who had previously received radioimmunotherapy. Subset analysis revealed that the rate of response in previous rituximab responders was 18%, lower than previously reported for this population (38, 39). However, long-term response assessments were not conducted in the study reported here; thus, late responses might have been missed. Higher rates of response were seen in patients with extended dosing; however, many of these responses occurred early in the course of therapy, suggesting that conclusions that can be reached from this study are limited related to the value of prolonged therapy on response. There were two responses in patients with a history of rituximab-refractory disease. Similar response rates were seen in a heterogeneous population of NHL patients treated with rituximab and s.c. 1018 ISIS (33). Overall, the heterogeneous nature of the patient population in this phase I trial; the small number of patients in each subgroup; and the design of the trial, which did not include monitoring for late responses or duration of response, precludes any meaningful assessment of the potential efficacy benefit from the addition of PF-3512676 to rituximab.

Immunologic assays of NK function, antibody-dependent cellular toxicity, and evaluation of changes in lymphocyte phenotype were not done as part of this study due to its multicenter design and associated difficulties with assay integrity due to specimen transport issues. Additionally, the principal goal of the study was to determine the safety and toxicity of the investigational agent under evaluation. However, such correlative information of CpG effects was previously reported in a study of single-agent i.v. PF-3512676 in NHL patients and in normal subjects treated with s.c. therapy (21, 29).

In summary, the current study was designed to assess the safety of combining PF-3512676, administered using three different delivery methods, with rituximab in patients with NHL. The theoretical concerns for tumor flare or intolerable rituximab infusion reactions were not realized. Although both i.v. and s.c. routes of administration for PF-3512676 were safe, there was a higher frequency of symptomatic adverse events with s.c. delivery, which, at high doses, challenged patient tolerability over time. Given the demonstration in previous studies that administration route and duration of therapy can impact on the biological activity of immunostimulatory CpG ODN, dedicated study of the various schedules in trials of focused disease populations powered to determine clinical efficacy will be required.


   Footnotes
 
Grant support: Coley Pharmaceutical Group, Wellesley, MA.

The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

Received 4/ 9/07; revised 7/10/07; accepted 8/22/07.


   References
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 Materials and Methods
 Results
 Discussion
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  1. Takeda K, Kaisho T, Akira S. Toll-like receptors. Annu Rev Immunol 2003;21:335–76.[CrossRef][Medline]
  2. Krieg AM. CpG motifs in bacterial DNA and their immune effects. Annu Rev Immunol 2002;20:709–60.[CrossRef][Medline]
  3. Bauer S, Kirschning CJ, Hacker H, et al. Human TLR9 confers responsiveness to bacterial DNA via species-specific CpG motif recognition. Proc Natl Acad Sci U S A 2001;98:9237–42.[Abstract/Free Full Text]
  4. Hornung V, Rothenfusser S, Britsch S, et al. Quantitative expression of toll-like receptor 1–10 mRNA in cellular subsets of human peripheral blood mononuclear cells and sensitivity to CpG oligodeoxynucleotides. J Immunol 2002;168:4531–7.[Abstract/Free Full Text]
  5. Kadowaki N, Ho S, Antonenko S, et al. Subsets of human dendritic cell precursors express different toll-like receptors and respond to different microbial antigens. J Exp Med 2001;194:863–9.[Abstract/Free Full Text]
  6. Decker T, Schneller F, Sparwasser T, et al. Immunostimulatory CpG-oligonucleotides cause proliferation, cytokine production, and an immunogenic phenotype in chronic lymphocytic leukemia B cells. Blood 2000;95:999–1006.[Abstract/Free Full Text]
  7. Jahrsdorfer B, Hartmann G, Racila E, et al. CpG DNA increases primary malignant B cell expression of costimulatory molecules and target antigens. J Leukoc Biol 2001;69:81–8.[Abstract/Free Full Text]
  8. Wooldridge JE, Weiner GJ. CpG DNA and cancer immunotherapy: orchestrating the antitumor immune response. Curr Opin Oncol 2003;15:440–5.[CrossRef][Medline]
  9. Jahrsdorfer B, Wooldridge JE, Blackwell SE, et al. Immunostimulatory oligodeoxynucleotides induce apoptosis of B cell chronic lymphocytic leukemia cells. J Leukoc Biol 2005;77:378–87.[Abstract/Free Full Text]
  10. Decker T, Hipp S, Kreitman RJ, Pastan I, Peschel C, Licht T. Sensitization of B-cell chronic lymphocytic leukemia cells to recombinant immunotoxin by immunostimulatory phosphorothioate oligodeoxynucleotides. Blood 2002;99:1320–6.[Abstract/Free Full Text]
  11. Wooldridge JE, Ballas Z, Krieg AM, Weiner GJ. Immunostimulatory oligodeoxynucleotides containing CpG motifs enhance the efficacy of monoclonal antibody therapy of lymphoma. Blood 1997;89:2994–8.[Abstract/Free Full Text]
  12. Rituxan (rituximab) [package insert]. San Diego (CA): Biogen Idec Inc; and San Francisco (CA): Genentech, Inc.; 2006.
  13. Anderson KC, Bates MP, Slaughenhoupt BL, Pinkus GS, Schlossman SF, Nadler LM. Expression of human B cell-associated antigens on leukemias and lymphomas: a model of human B cell differentiation. Blood 1984;63:1424–33.[Abstract/Free Full Text]
  14. Riley JK, Sliwkowski MX. CD20: a gene in search of a function. Semin Oncol 2000;27:17–24.[Medline]
  15. McLaughlin P, Grillo-Lopez AJ, Link BK, et al. Rituximab chimeric anti-CD20 monoclonal antibody therapy for relapsed indolent lymphoma: half of patients respond to a four-dose treatment program. J Clin Oncol 1998;16:2825–33.[Abstract]
  16. Vose JM, Link BK, Grossbard ML, et al. Phase II study of rituximab in combination with CHOP chemotherapy in patients with previously untreated, aggressive non–Hodgkin's lymphoma. J Clin Oncol 2001;19:389–97.[Abstract/Free Full Text]
  17. Coiffier B, Haioun C, Ketterer N, et al. Rituximab (anti-CD20 monoclonal antibody) for the treatment of patients with relapsing or refractory aggressive lymphoma: a multicenter phase II study. Blood 1998;92:1927–32.[Abstract/Free Full Text]
  18. Davis TA, White CA, Grillo-Lopez AJ, et al. Single-agent monoclonal antibody efficacy in bulky non–Hodgkin's lymphoma: results of a phase II trial of rituximab. J Clin Oncol 1999;17:1851–7.[Abstract/Free Full Text]
  19. van Ojik HH, Bevaart L, Dahle CE, et al. CpG-A and B oligodeoxynucleotides enhance the efficacy of antibody therapy by activating different effector cell populations. Cancer Res 2003;63:5595–600.[Abstract/Free Full Text]
  20. Carpentier AF, Auf G, Delattre JY. CpG-oligonucleotides for cancer immunotherapy: review of the literature and potential applications in malignant glioma. Front Biosci 2003;8:3115–27.
  21. Link BK, Ballas ZK, Weisdorf D, et al. Oligodeoxynucleotide CpG 7909 delivered as intravenous infusion demonstrated immunologic modulation in patients with previously treated non–Hodgkin lymphoma. J Immunother 2006;29:558–68.[Medline]
  22. Pashenkov M, Goess G, Wagner C, et al. Phase II trial of a toll-like receptor 9-activating oligonucleotide in patients with metastatis melanoma. J Clin Oncol 2006;24:5716–24.[Abstract/Free Full Text]
  23. Krieg AM. Antitumor applications of stimulating toll-like receptor 9 with CpG oligodeoxynucleotides. Curr Oncol Rep 2004;6:88–95.[Medline]
  24. Wagner SN, Pashenkov M, Goess C, Schneeberger A, Krieg AM, Stingl G. TLR9-targeted CpG immunostimulatory treatment of metastatic melanoma: a phase II trial with CpG 7909 (Promune) [abstract 7513]. J Clin Oncol 2004;23:710.
  25. Thompson JA, Kuzel T, Bukowski R, Masciari F, Schmalbach T. Phase Ib trial of a targeted TLR9 CpG immunomodulator (CpG 7909) in advanced renal cell carcinoma (RCC) [abstract 4644]. J Clin Oncol 2004;23:416.
  26. Kim Y, Girardi M, McAuley S, Schmalbach T. Cutaneous T-cell lymphoma (CTCL) responses to a TLR9 agonist CpG immunomodulator (CpG 7909), a phase I study [abstract 6600]. J Clin Oncol 2004;22:580.[Free Full Text]
  27. Trefzer U, Kors C, Pelzer K, Walden P, Sterry W, O'Keefe E. Preliminary results of a phase I trial of intralesional injection of CpG 7909 in patients with basal cell carcinoma or melanoma [abstract 1902]. Proc Am Soc Clin Oncol 2002;21:24b.
  28. Warren TL, Weiner GJ. Synergism between cytosine-guanine oligodeoxynucleotides and monoclonal antibody in the treatment of lymphoma. Semin Oncol 2002;29:93–7.[CrossRef][Medline]
  29. Krieg AM, Efler SM, Wittpoth M, et al. Induction of systemic TH1-like innate immunity in normal volunteers following subcutaneous but not intravenous administration of CpG 7909, a synthetic B-class CpG oligodeoxynucleotide TLR9 agonist. J Immunother 2004;27:460–71.[Medline]
  30. Cheson BD, Horning SJ, Coiffier B, et al. Report of an international workshop to standardize response criteria for non–Hodgkin's lymphomas. J Clin Oncol 1999;17:1244–53.[Abstract/Free Full Text]
  31. Behboudi S, Chao D, Klenerman P, Austyn J. The effects of DNA containing CpG motif on dendritic cells. Immunology 2000;99:361–6.[CrossRef][Medline]
  32. Vabulas RM, Pircher H, Lipford GB, Hacker H, Wagner H. CpG-DNA activates in vivo T cell epitope presenting dendritic cells to trigger protective antiviral cytotoxic T cell responses. J Immunol 2000;164:2372–8.[Abstract/Free Full Text]
  33. Friedberg JW, Kim H, McCauley M, et al. Combination immunotherapy with a CpG oligonucleotide (1018 ISS) and rituximab in patients with non–Hodgkin lymphoma: increased interferon-{alpha}/ß-inducible gene expression, without significant toxicity. Blood 2005;105:489–95.[Abstract/Free Full Text]
  34. Ehrenfeld M, Abu-Shakra M, Buskila D, Shoenfeld Y. The dual association between lymphoma and autoimmunity. Blood Cells Mol Dis 2001;27:750–6.[CrossRef][Medline]
  35. Hagler KT, Lynch JW, Jr. Paraneoplastic manifestations of lymphoma. Clin Lymphoma 2004;5:29–36.[Medline]
  36. Varoczy L, Gergely L, Zeher M, Szegedi G, Illes A. Malignant lymphoma-associated autoimmune diseases—a descriptive epidemiological study. Rheumatol Int 2002;22:233–7.[CrossRef][Medline]
  37. Maloney DG, Grillo-Lopez AJ, White CA, et al. IDEC-C2B8 (Rituximab) anti-CD20 monoclonal antibody therapy in patients with relapsed low-grade non–Hodgkin's lymphoma. Blood 1997;90:2188–95.[Abstract/Free Full Text]
  38. Davis TA, Grillo-Lopez AJ, White CA, et al. Rituximab anti-CD20 monoclonal antibody therapy in non–Hodgkin's lymphoma: safety and efficacy of re-treatment. J Clin Oncol 2000;18:3135–43.[Abstract/Free Full Text]
  39. Igarashi T, Ohtsu T, Fujii H, et al. Re-treatment of relapsed indolent B-cell lymphoma with rituximab. Int J Hematol 2001;73:213–21.[Medline]



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