A Phase 2, International, Multicenter, Open-label Clinical Trial of Subcutaneous Tbo-Filgrastim in Pediatric Patients With Solid Tumors Undergoing Myelosuppressive Chemotherapy.

This phase 2, multicenter, open-label trial investigated the safety and tolerability of tbo-filgrastim in pediatric patients receiving myelosuppressive chemotherapy. In total, 50 patients 1 month to below 16 years of age with solid tumors without bone marrow involvement were stratified into 3 age groups (2 infants, 30 children, 18 adolescents) and prophylactically administered tbo-filgrastim 5 µg/kg body weight once daily subcutaneously. The administration started after the last chemotherapy treatment in week 1 of the first cycle and continued until the expected neutrophil nadir had passed, and the neutrophil count had recovered to 2.0×10/L. The primary endpoint was safety and tolerability of tbo-filgrastim; secondary endpoints included efficacy. The mean (SD) number of doses administered was 9.2 (2.83) in children and 7.3 (1.88) in adolescents. Serious treatment-emergent adverse events were reported in 24% of patients; the most common were febrile neutropenia (FN) (12%), anemia (8%), and thrombocytopenia (8%). Nine patients (18%) experienced mild treatment-related treatment-emergent adverse events; the most common were musculoskeletal and connective tissue disorders (8%). No deaths or withdrawals occurred. The incidence of severe neutropenia (SN) was 52% and the mean (SD) duration of SN was 1.8 (2.21) days; FN incidence was 26%. A daily dose of tbo-filgrastim 5 µg/kg body weight administered to pediatric patients demonstrated a safety profile consistent with the safety profile in adult patients. The incidence of FN was on the lower end of the range reported in the literature and the SN results provide supportive data on the efficacy of tbo-filgrastim in pediatric patients.

Real-world safety experience of tevagrastim/ratiograstim/biograstim and tbo-filgrastim, short-acting recombinant human granulocyte colony-stimulating factors.

PURPOSE: Recombinant granulocyte colony-stimulating factors (rG-CSFs), such as filgrastim, are administered to prevent complications in patients receiving chemotherapy. In Europe, a biosimilar to filgrastim, tevagrastim/ratiograstim/biograstim, was approved in 2008. In the USA, the same product was approved as tbo-filgrastim under a 351(a) biologic license application in 2012 with the brand name Granix®. Postmarket surveillance remains a priority for monitoring the safety of biologics and biosimilars to identify rare and immunogenicity-related events. We report the global and US pharmacovigilance data for tevagrastim/ratiograstim/biograstim and tbo-filgrastim, respectively. METHODS: Cumulative exposure and adverse event data from initial approval in Europe to December 31, 2016, were collected globally from spontaneous reports submitted by healthcare professionals and consumers, scientific literature, competent authorities, and solicited case reports from non-interventional studies. A separate search was conducted on the global data set to identify reports originating from the USA and Puerto Rico to describe the US experience. RESULTS: Overall, the global safety profile of tevagrastim/ratiograstim/biograstim in the postmarket, real-world setting was comparable to clinical trial experience. Postmarket safety experience of tbo-filgrastim in the USA was consistent with global data. The most common SAEs were febrile neutropenia and decreased white blood cell count. The most common non-serious event was bone pain. There was no evidence of immunogenicity. CONCLUSIONS: This pharmacovigilance analysis indicates that postmarket experience of tevagrastim/ratiograstim/biograstim and tbo-filgrastim is consistent with clinical trials. Adverse reactions associated with the originator rG-CSF (capillary leak syndrome and glomerulonephritis) have not been observed with tevagrastim/ratiograstim/biograstim or tbo-filgrastim during the postmarket period.

Chemotherapy-associated treatment burden in breast cancer patients receiving lipegfilgrastim or pegfilgrastim: secondary efficacy data from a phase III study.

PURPOSE: Lipegfilgrastim is a once-per-cycle glycoPEGylated granulocyte colony-stimulating factor (G-CSF). Noninferiority of lipegfilgrastim versus pegfilgrastim was demonstrated in a phase III trial in chemotherapy (CTx)-naïve breast cancer patients. Secondary outcomes relating to treatment burden are reported here. METHODS: Patients with high-risk stage II, III, or IV breast cancer were randomized to receive lipegfilgrastim 6 mg (n = 101) or pegfilgrastim 6 mg (n = 101) subcutaneously on day 2 of each CTx cycle. Doxorubicin 60 mg/m(2) plus docetaxel 75 mg/m(2) commenced on day 1, for up to four cycles. Secondary end points included days in the hospital or intensive care unit (ICU), use of intravenous antibiotics for febrile neutropenia (FN) or related infections, and measures of CTx delivery (dose delays, reductions, and omissions). RESULTS: One lipegfilgrastim recipient and two pegfilgrastim recipients were hospitalized in cycle 1 because of FN or associated infection. The lipegfilgrastim-treated patient spent 1 day in the ICU for FN, and the two pegfilgrastim-treated patients were hospitalized for FN for 5 and 6 days, respectively. All hospitalized patients received antibiotics. An additional pegfilgrastim-treated patient received antibiotics but was not hospitalized. Most patients received CTx as scheduled; over 98% received their planned doxorubicin and docetaxel doses in all cycles. In the lipegfilgrastim group, no patients had a CTx dose reduced or omitted; eight patients in the pegfilgrastim group had a CTx dose reduced or omitted during cycles 2-4. CONCLUSIONS: The burden of treatment associated with myelosuppressive CTx was similar in breast cancer patients treated with lipegfilgrastim or pegfilgrastim.

Efficacy and safety of lipegfilgrastim compared with placebo in patients with non-small cell lung cancer receiving chemotherapy: post hoc analysis of elderly versus younger patients.

PURPOSE: Lipegfilgrastim, a glycoPEGylated recombinant granulocyte colony-stimulating factor (G-CSF), reduces neutropenia duration and febrile neutropenia (FN) incidence in patients with cancer receiving myelosuppressive chemotherapy. A phase 3 trial of lipegfilgrastim was conducted in patients with advanced non-small cell lung cancer (NSCLC) receiving cisplatin/etoposide (which produces mild-to-moderate myelosuppression). Because patients aged >65 years are at higher risk for FN versus younger patients, this post hoc analysis compared outcomes in elderly (>65 years) versus younger participants in this trial. METHODS: Patients were randomized 2:1 to receive a once-per-cycle single subcutaneous injection of lipegfilgrastim 6 mg or placebo, with up to 4 cycles of every-3-week cisplatin (day 1) and etoposide (days 1-3). The primary end point was FN incidence during cycle 1. Outcomes were compared across treatment groups and by age groups (≤65 and >65 years). RESULTS: For patients aged ≤65 years, FN incidence during cycle 1 was similar in the lipegfilgrastim and placebo groups (3.0 vs 3.2 %, respectively), whereas for elderly patients, there was a reduction in FN incidence with lipegfilgrastim (0 vs 13.3 %, respectively). In both age subgroups, lipegfilgrastim showed a propensity to reduce the incidence and duration of severe neutropenia, time to absolute neutrophil count (ANC) recovery, and depth of ANC nadir. Adverse events were generally similar between groups. CONCLUSIONS: This analysis suggests that in patients with a higher FN risk, such as the elderly patients of this study, lipegfilgrastim reduces not only the duration of severe neutropenia but also the incidence of FN.

A randomized, double-blind, active control, multicenter, dose-finding study of lipegfilgrastim (XM22) in breast cancer patients receiving myelosuppressive therapy.

This dose-ranging study was conducted to identify the optimal fixed dose of lipegfilgrastim compared with pegfilgrastim 6.0 mg for the provision of neutrophil support during myelosuppressive chemotherapy in patients with breast cancer. A phase 2 study was conducted in which 208 chemotherapy-naive patients were randomized to receive lipegfilgrastim 3.0, 4.5, or 6.0 mg or pegfilgrastim 6.0 mg. Study drugs were administered as a single subcutaneous injection on day 2 of each chemotherapy cycle (doxorubicin/docetaxel on day 1 for four 3-week cycles). The primary outcome measure was duration of severe neutropenia (DSN) in cycle 1. Patients treated with lipegfilgrastim experienced shorter DSN in cycle 1 with higher doses. The mean DSN was 0.76 days in the lipegfilgrastim 6.0-mg group and 0.87 days in the pegfilgrastim 6.0-mg group, with no significant differences between treatment groups. Treatment with lipegfilgrastim 6.0 mg was consistently associated with a higher absolute neutrophil count (ANC) at nadir, shorter ANC recovery time, and a similar safety and tolerability profile compared with pegfilgrastim. This phase 2 study demonstrated that lipegfilgrastim 6.0 mg is the optimal dose for patients with breast cancer and provides neutrophil support that is at least equivalent to the standard 6.0-mg fixed dose of pegfilgrastim.

Efficacy and safety of lipegfilgrastim versus pegfilgrastim: a randomized, multicenter, active-control phase 3 trial in patients with breast cancer receiving doxorubicin/docetaxel chemotherapy.

BACKGROUND: Lipegfilgrastim is a novel glyco-pegylated granulocyte-colony stimulating factor in development for neutropenia prophylaxis in cancer patients receiving chemotherapy. This phase III, double-blind, randomized, active-controlled, noninferiority trial compared the efficacy and safety of lipegfilgrastim versus pegfilgrastim in chemotherapy-naïve breast cancer patients receiving doxorubicin/docetaxel chemotherapy. METHODS: Patients with high-risk stage II, III, or IV breast cancer and an absolute neutrophil count ≥1.5 × 109 cells/L were randomized to a single 6-mg subcutaneous injection of lipegfilgrastim (n = 101) or pegfilgrastim (n = 101) on day 2 of each 21-day chemotherapy cycle (4 cycles maximum). The primary efficacy endpoint was the duration of severe neutropenia during cycle 1. RESULTS: Cycle 1: The mean duration of severe neutropenia for the lipegfilgrastim and pegfilgrastim groups was 0.7 and 0.8 days, respectively (λ = -0.218 [95% confidence interval: -0.498%, 0.062%], p = 0.126), and no severe neutropenia was observed in 56% and 49% of patients in the lipegfilgrastim and pegfilgrastim groups, respectively. All cycles: In the efficacy population, febrile neutropenia occurred in three pegfilgrastim-treated patients (all in cycle 1) and zero lipegfilgrastim-treated patients. Drug-related adverse events in the safety population were reported in 28% and 26% of patients in the lipegfilgrastim and pegfilgrastim groups, respectively. CONCLUSION: This study demonstrates that lipegfilgrastim 6 mg is as effective as pegfilgrastim in reducing neutropenia in patients with breast cancer receiving myelosuppressive chemotherapy. TRIAL REGISTRATION: Eudra EEACTA200901599910.

Immunogenicity assessment of tbo-filgrastim in cancer patients receiving chemotherapy.

AIM: This integrated analysis examined the immunogenicity of tbo-filgrastim and its potential clinical impact in three Phase III randomized studies in patients with breast cancer, lung cancer and non-Hodgkin lymphoma receiving chemotherapy. RESULTS: Treatment-emergent antidrug antibodies (ADA) occurred in 3/213 (1.4%) breast cancer patients, 2/160 (1.3%) lung cancer patients and 1/63 (1.6%) patients with non-Hodgkin lymphoma. None of the treatment-emergent ADA showed cross-reactivity toward native granulocyte-colony stimulating factors or exhibited neutralizing activity against tbo-filgrastim. Among patients with treatment-emergent ADA, there was no treatment-related hypersensitivity or anaphylaxis and no evidence of loss of clinical efficacy. CONCLUSION: Tbo-filgrastim has demonstrated low immunogenicity in cancer patients receiving chemotherapy and ADA response does not impact safety and efficacy in the patients.

A pharmacokinetic study of lipegfilgrastim in children with Ewing family of tumors or rhabdomyosarcoma.

PURPOSE: Neutropenia is a common complication from chemotherapy, limiting optimal dosing and treatment. Lipegfilgrastim is a long-acting granulocyte colony-stimulating factor developed for the management of chemotherapy-induced neutropenia. The objectives of this phase 1, multinational, open-label, single-arm study were to characterize the pharmacokinetics (PK) and pharmacodynamics (PD) of a single body weight-adjusted dose of lipegfilgrastim and to evaluate the efficacy, safety, and tolerability of the drug in children with Ewing family of tumors or rhabdomyosarcoma treated with myelosuppressive chemotherapy. METHODS: Enrolled patients received lipegfilgrastim (100 µg/kg) 24 h after the last chemotherapy treatment in week 1. Patients were stratified into three age groups: 2 to <6, 6 to <12, and 12 to <18 years. Blood samples for PK analyses were obtained at baseline and at 3, 8, 24, 30, 48, 72, 96, 144, and 240 h postdose for the two oldest groups and up to 144 h in the youngest group. RESULTS: Twenty-one patients were enrolled and received lipegfilgrastim, seven in each age group. Lipegfilgrastim exposure levels were comparable across age groups, with concentrations maintained over a prolonged period after a single injection. Differences in PD were mainly associated with chemotherapy type. Most investigator-reported adverse events were attributed to chemotherapy and not to lipegfilgrastim. Severe adverse events were noted in 57% of patients; febrile neutropenia, leukopenia, neutropenia, and thrombocytopenia were more frequent among the oldest patients. CONCLUSIONS: Results support the use of a body weight-adjusted dose to achieve equivalent initial peak exposure levels of lipegfilgrastim in children of various ages.

Immunogenicity Assessment of Lipegfilgrastim in Patients with Breast Cancer Receiving Chemotherapy.

Lipegfilgrastim is a long-acting, once-per-cycle, glycopegylated recombinant granulocyte colony-stimulating factor (G-CSF) used to prevent neutropenia in patients receiving myelosuppressive chemotherapy. This integrated analysis examined the immunogenicity of lipegfilgrastim and its potential clinical impact in two double-blind randomized studies (phases II and III) of patients with breast cancer receiving chemotherapy. Serum samples were analyzed using sequential assays for screening, confirmation, antibody titer, and characterization of antidrug antibodies (ADA). Neutropenia-related efficacy measures were reviewed for each ADA-positive patient. Among 255 patients receiving lipegfilgrastim (154 in phase II, 101 in phase III) and 155 patients receiving pegfilgrastim (54 in phase II, 101 in phase III), the incidence of treatment-emergent ADA was low and similar between the lipegfilgrastim (phase II: 1.3%; phase III: 1.0%) and pegfilgrastim (phase II: 1.9%; phase III: 1.0%) arms. None of the treatment-emergent ADA-positive samples exhibited neutralizing activity against lipegfilgrastim, pegfilgrastim, or glycosylated G-CSF in a cell-based neutralizing antibody assay. No changes were observed in neutropenia-related efficacy measures among ADA-positive patients, and no treatment-related hypersensitivity or anaphylaxis occurred. These results indicate that there is no apparent impact of ADA on lipegfilgrastim efficacy and safety.

Phase III, randomized, double-blind, placebo-controlled, multicenter study of lipegfilgrastim in patients with non-small cell lung cancer receiving myelosuppressive therapy.

PURPOSE: The aim of this study was to demonstrate lipegfilgrastim superiority versus placebo in adults with non-small cell lung cancer receiving myelosuppressive chemotherapy. METHODS: This phase III, double-blind study randomized chemotherapy-naive patients to receive cisplatin and etoposide with either lipegfilgrastim 6 mg or placebo. Because of the placebo control, patients at individual high risk for febrile neutropenia (FN; ≥20%) were excluded. Study drug was administered on day 4 (24 h after chemotherapy) of a 21-day cycle for ≤4 cycles. Primary efficacy measure was FN incidence in cycle 1. Secondary assessments included duration of severe neutropenia (DSN), absolute neutrophil count (ANC) profile, and adverse events (AEs). RESULTS: The study included 375 patients (lipegfilgrastim, n = 250; placebo, n = 125). Lipegfilgrastim superiority for FN incidence in cycle 1 was not achieved but incidence was lower (2.4%) versus placebo (5.6%). Cycle 1 mean DSN was significantly shorter for lipegfilgrastim (0.6 ± 1.1 days) versus placebo (2.3 ± 0.5 days; p < 0.0001). Incidence of severe neutropenia was significantly lower for lipegfilgrastim versus placebo overall and in each cycle (all, p < 0.0001). Mean ANC nadir was lowest in cycle 1 but significantly higher for lipegfilgrastim (1.60 ± 1.64) than placebo (0.67 ± 0.85; p < 0.0001). Mean time to ANC recovery was shorter with lipegfilgrastim in each cycle. Treatment-emergent AEs were similar between treatment groups. CONCLUSIONS: Lipegfilgrastim was not statistically superior to placebo for incidence of FN in cycle 1, but was more effective in reducing incidence of severe neutropenia, DSN, and time to ANC recovery, with an acceptable safety profile. Controlled-trials.com identifier: ISRCTN55761467.

Lipegfilgrastim: pharmacodynamics and pharmacokinetics for body-weight-adjusted and 6 mg fixed doses in two randomized studies in healthy volunteers.

OBJECTIVE: Two phase I, single-blind (subject blinded to treatment), randomized studies were conducted to assess the pharmacodynamics, pharmacokinetics, safety, and tolerability of lipegfilgrastim compared with pegfilgrastim in healthy adult volunteers. METHODS: Study 1 consisted of a pilot safety phase (N = 8) during which subjects received a single body-weight-adjusted subcutaneous dose of lipegfilgrastim 25 µg/kg and a dose escalation phase (N = 45) wherein subjects received lipegfilgrastim 50 or 100 µg/kg or pegfilgrastim 100 µg/kg. Study 2 was a single-blind, fixed-dose study (N = 36) comparing subcutaneous lipegfilgrastim 6 mg and pegfilgrastim 6 mg. RESULTS: Cumulative exposure (AUC0-t last and AUC 0-∞) and peak exposure (Cmax) were higher for lipegfilgrastim than pegfilgrastim after both weight-adjusted and fixed dosing. In both studies, the terminal elimination half-life of lipegfilgrastim was 5-10 hours longer than the terminal elimination half-life for pegfilgrastim at the maximum dose, and the time to maximum serum concentration (tmax) was observed later for lipegfilgrastim than for pegfilgrastim. The area over the baseline effect curve (AOBEC) for absolute neutrophil count (ANC) was approximately 30% greater after lipegfilgrastim dosing compared with the same dose of pegfilgrastim at the maximum dose. Both drugs were well tolerated, with a similar occurrence of adverse events between treatment groups. Key limitations of these studies include the small numbers of subjects and differences in dosage regimens between the two studies. CONCLUSIONS: In these studies, lipegfilgrastim provided a longer-lasting increase in ANC compared with pegfilgrastim at an equivalent dose, without increasing the peak ANC values. This may reflect the higher cumulative exposure and slower clearance (therefore longer body residence) of lipegfilgrastim. These data support the use of single-dose lipegfilgrastim 6 mg in subsequent phase III trials as prophylactic treatment for patients receiving myelosuppressive chemotherapy.

Efficacy and safety of balugrastim compared with pegfilgrastim in patients with breast cancer receiving chemotherapy.

BACKGROUND: Recombinant granulocyte colony-stimulating factors (G-CSFs) reduce the incidence and duration of chemotherapy-induced neutropenia and febrile neutropenia when given as adjunct therapy to patients receiving myelosuppressive chemotherapy. Balugrastim is a long-acting G-CSF composed of a genetic fusion between recombinant human serum albumin and G-CSF. We compared the efficacy and safety of balugrastim and pegfilgrastim, a long-acting pegylated recombinant G-CSF, in patients with breast cancer who were scheduled to receive chemotherapy. PATIENTS AND METHODS: In this double-blind randomized phase III trial, patients with ≥ 1.5 × 10(9) neutrophils/L were randomly assigned to subcutaneous injections of balugrastim 40 mg (n = 153) or pegfilgrastim 6 mg (n = 151). The primary efficacy end point was the duration of severe neutropenia (DSN) (days with an absolute neutrophil count [ANC] < 0.5 × 10(9) cells/L) during cycle 1. Efficacy analyses were performed in the per-protocol (PP) population. In a separate open-label single-arm study, newly recruited patients (n = 77) received balugrastim 40 mg and were included in the safety analysis. RESULTS: The mean DSN in cycle 1 was 1.1 days in the balugrastim group and 1.0 days in the pegfilgrastim group (95% confidence interval [CI], -0.13-0.37). Two and 4 patients, respectively, had febrile neutropenia during cycle 1. Twenty percent of patients in the balugrastim group and 19% in the pegfilgrastim group had adverse events (AEs) considered to be related to study medication; 3.9% and 4.7% of patients, respectively, experienced serious AEs. CONCLUSIONS: This study demonstrates the comparable safety and efficacy profile of balugrastim and pegfilgrastim and the noninferiority of balugrastim for reduction in DSN. There were no unexpected safety events.

Epoetin Theta with a New Dosing Schedule in Anaemic Cancer Patients Receiving Nonplatinum-Based Chemotherapy: A Randomised Controlled Trial.

INTRODUCTION: Recombinant human erythropoietin (r-HuEPO) is used to treat symptomatic anaemia due to chemotherapy. A new r-HuEPO, Epoetin theta (Eporatio®), was investigated and compared to placebo in a randomised, double-blind clinical trial in adult cancer patients receiving nonplatinum-based chemotherapy. The primary efficacy endpoint was the responder rate (complete haemoglobin (Hb) response, i.e., Hb increase ≥2 g/dl) without the benefit of a transfusion within the previous 4 weeks. RESEARCH DESIGN AND METHODS: 186 patients were randomised to s.c. treatment for 12 weeks with either Epoetin theta (N = 95) or placebo (N = 91). The starting dose was 20,000 IU once weekly Epoetin theta or placebo. RESULTS: The incidence of complete Hb responders was significantly higher in the Epoetin theta group than in the placebo group (72.6 vs. 25.3%, P < 0.0001). More patients in the placebo group than in the Epoetin theta group received blood transfusions after randomisation (23 patients, 25.3% vs. 13 patients, 13.7%, P = 0.0277). The majority of patients with a complete Hb response had 20,000 IU/week as their maximum dose prior to response, indicating that a dose of 20,000 IU is an appropriate starting dose. The overall frequencies of adverse events (AEs) were similar in both treatment groups. Hypertension was the only AE that was more frequent in the Epoetin theta group compared to the placebo group (8.4 vs. 1.1%). CONCLUSIONS: Epoetin theta showed a superior efficacy to placebo in terms of complete Hb response without blood transfusion within the previous 4 weeks. Treatment with Epoetin theta resulted in a statistically significant increase in mean haemoglobin levels compared to placebo. The overall frequencies of adverse events were similar in both treatment groups.

Epoetin Theta in Anaemic Cancer Patients Receiving Platinum-Based Chemotherapy: A Randomised Controlled Trial.

INTRODUCTION: Recombinant human erythropoietin (r-HuEPO) is used to treat symptomatic anaemia due to chemotherapy. A new r-HuEPO, Epoetin theta (Eporatio®), was investigated and compared to placebo and Epoetin beta in a randomised, double-blind clinical trial in adult cancer patients receiving platinum-based chemotherapy, using a fixed weekly starting dose of 20,000 IU Epoetin theta. The primary efficacy endpoint was the responder rate (complete Hb response, Hb increase ≥ 2 g/dL). RESEARCH DESIGN AND METHODS: 223 patients were randomised to s.c. treatment for 12 weeks with either Epoetin theta (n = 76) once per week, Epoetin beta (n = 73) three times per week or placebo (n = 74). The starting dose was 20,000 IU once weekly Epoetin theta or 450 IU/kg(BW) per week Epoetin beta administered in 3 equal weekly doses. RESULTS: In the Epoetin theta group were significantly more responders than in the placebo group (65.8 vs. 20.3%, P < 0.0001). Epoetin beta was also more effective than placebo (71.2 vs. 20.3%, P < 0.0001). The mean weekly dose at the time of complete Hb response was lower in the Epoetin theta group (30,000 IU) than in the Epoetin beta group (42,230 IU). Epoetin theta was clearly more effective than placebo. CONCLUSION: This small study showed, that Epoetin theta is a safe and effective treatment of symptomatic anaemia due to platinum-based chemotherapy in cancer patients.

The gastrointestinal tolerability of the LOX/COX inhibitor, licofelone, is similar to placebo and superior to naproxen therapy in healthy volunteers: results from a randomized, controlled trial.

OBJECTIVES: Concerns exist over the safety of conventional nonsteroidal antiinflammatory drugs (NSAIDs) and selective cyclooxygenase (COX)-2 inhibitors. In experimental models, licofelone, a competitive inhibitor of 5-lipoxygenase (5-LOX) and COX-1/-2, has been shown to have good gastrointestinal and general tolerability and analgesic and antiinflammatory properties. The aim of the present endoscopy trial was to investigate the gastroduodenal tolerability of licofelone compared to placebo and naproxen in healthy volunteers. METHODS: In this randomized, parallel-group trial, healthy volunteers received licofelone 200 mg b.i.d. (n = 30), licofelone 400 mg b.i.d. (n = 30), naproxen 500 mg b.i.d. (n = 30), or placebo (n = 31). Tolerability was assessed by gastro/duodenoscopy following 4 wk of treatment. Laboratory parameters and the incidence of ulcers and adverse events were recorded. RESULTS: Ulcers were observed in 20% of the naproxen-treated volunteers, compared with 0% of those receiving licofelone 200 mg, licofelone 400 mg, and placebo (p= 0.024). Posttreatment mean gastric Lanza scores were similar for volunteers who received placebo or either dose of licofelone, while Lanza scores were significantly worse following naproxen therapy (p < 0.00001). The gastric mucosa was normal in 93%, 89%, and 90% of volunteers who received licofelone 200 mg, licofelone 400 mg, or placebo, respectively, compared with 37% of volunteers receiving naproxen. The incidence of adverse events did not differ significantly between licofelone 200 mg or naproxen therapy. No clinically relevant changes in laboratory parameters were observed with licofelone or naproxen therapy. CONCLUSIONS: The results from this trial indicate that licofelone has a potential gastrointestinal safety advantage over conventional NSAID therapy, as licofelone was associated with significantly superior gastric tolerability and a lower incidence of ulcers compared with naproxen in healthy volunteers. Further trials will be required to investigate the safety and efficacy of licofelone in the treatment of diseases such as osteoarthritis.