First-in-human randomized clinical trials of the safety and efficacy of tanezumab for treatment of chronic knee osteoarthritis pain or acute bunionectomy pain.

INTRODUCTION: The neurotrophin nerve growth factor has a demonstrated role in pain transduction and pathophysiology. OBJECTIVES: Two randomized, double-blind, placebo-controlled, phase 1 studies were conducted to evaluate safety, tolerability, and analgesic efficacy of single doses of tanezumab, a humanized anti-nerve growth factor monoclonal antibody, in chronic or acute pain. METHODS: In the first study (CL001), patients with moderate to severe pain from osteoarthritis (OA) of the knee received a single intravenous infusion of tanezumab (3-1000 µg/kg) or placebo in a dose-escalation (part 1; N = 42) or parallel-arm (part 2; N = 79) study design. The second study (CL002) was a placebo-controlled dose-escalation (tanezumab 10-1000 µg/kg; N = 50) study in patients undergoing bunionectomy surgery. RESULTS: Adverse event rates were generally similar across treatments. Most adverse events were generally mild to moderate in severity and no patients discontinued as a result of adverse events. Adverse events of abnormal peripheral sensation were more common with higher doses of tanezumab (≥100 µg/kg) than with placebo. These were generally mild to moderate in severity. Tanezumab provided up to 12 weeks of effective analgesia for OA knee pain, with statistically significant improvements at doses ≥100 µg/kg (P < 0.05). By contrast, no trend for analgesic activity was found when tanezumab was administered 8 to 16 hours before bunionectomy. CONCLUSIONS: The demonstration of a favorable safety profile and clinical efficacy in OA pain supports clinical development of tanezumab as a potential treatment for chronic pain conditions.

The case for soluble Aß oligomers as a drug target in Alzheimer's disease.

Soluble Aß oligomers are now widely recognized as key pathogenic structures in Alzheimer's disease. They inhibit synaptic function, leading to early memory deficits and synaptic degeneration, and they trigger the downstream neuronal signaling responsible for phospho-tau Alzheimer's pathology. The marginal effects observed in recent clinical studies of solanezumab, targeting monomeric Aß, and bapineuzumab, targeting amyloid plaques, prompted expert comments that drug discovery efforts in Alzheimer's disease should focus on soluble forms of Aß rather than fibrillar Aß deposits found in amyloid plaques. Accumulating scientific data suggest that soluble Aß oligomers represent the optimal intervention target within the amyloid manifold. Active drug discovery approaches include antibodies that selectively capture soluble Aß oligomers, selective modifiers of oligomer assembly, and receptor antagonists. The onset of symptomatic clinical benefit is expected to be rapid for such agents, because neuronal memory signaling should normalize on blockage of soluble Aß oligomers. This key feature is not shared by amyloid-lowering therapeutics, and it should translate into streamlined clinical development for oligomer-targeting drugs. Oligomer-targeting drugs should also confer long-term disease modification and slowing of disease progression, because they prevent the downstream signaling responsible for phospho-tau mediated cytoskeletal degeneration.

A review and update of the current status of the vasculature-disabling agent combretastatin-A4 phosphate (CA4P).

Vascular-disrupting strategies impair a tumor's blood vessel network, which is essential for tumor progression and metastasis. Vascular-disrupting agents (VDAs) cause a rapid and selective vascular shutdown in tumors to produce extensive secondary neoplastic cell death due to ischemia. A lead agent in this therapeutic strategy is the tubulin depolymerizing agent combretastatin-A4 phosphate (CA4P). Used alone, CA4P induces extensive necrosis in a wide variety of preclinical cancer models and significant blood flow reductions in the patient tumors. Preclinical and clinical data further indicate that CA4P can effectively be combined with chemotherapy or radiotherapy. Finally, the potential of combining VDAs with antiangiogenic therapies has shown considerable promise in preclinical models and such combinations are now beginning to be evaluated in patients.

Safety of efalizumab in adults with chronic moderate to severe plaque psoriasis: a phase IIIb, randomized, controlled trial.

BACKGROUND: To provide safety data for efalizumab, a recombinant humanized monoclonal IgG(1) antibody, in adults with chronic plaque psoriasis. METHODS: A 12-week, Phase IIIb, randomized, double-blind, parallel-group, placebo-controlled trial. At 58 study sites in the USA and Canada, 686 patients with moderate to severe chronic plaque psoriasis received an initial conditioning dose of efalizumab 0.7 mg/kg subcutaneously (SC) followed by either 11 weekly doses of efalizumab 1 mg/kg SC or matching placebo. Main outcome measures were safety and tolerability outcomes (primary) and efficacy outcomes (secondary). RESULTS: During 12 weeks of therapy with efalizumab or placebo, the incidence of clinical adverse events was 82.2% and 72.9%, respectively; the incidence of serious adverse events was 1.8% and 3.4%, respectively; and the incidence of nonserious adverse events leading to withdrawal was 1.8% and 1.7%, respectively. In the efalizumab group, there were no clinically significant changes in vital signs or laboratory parameters and no evidence of end-organ toxicities. A significantly higher proportion of patients receiving efalizumab than those receiving placebo achieved > or = 75% improvement in the Psoriasis Area and Severity Index (PASI) (P < 0.001), > or = 50% improvement in PASI (P < 0.001), and a static Physician's Global Assessment rating of Minimal or Clear (P < 0.001). The mean improvement in the Psoriasis Symptom Assessment was significantly greater in the efalizumab group (P < 0.001). CONCLUSIONS: Efalizumab treatment SC for 12 weeks was safe, well tolerated, and effective in patients with moderate to severe chronic plaque psoriasis.

Novel class of pain drugs based on antagonism of NGF.

Nerve growth factor (NGF) was identified originally as a survival factor for sensory and sympathetic neurons in the developing nervous system. In adults, NGF is not required for survival but it has a crucial role in the generation of pain and hyperalgesia in several acute and chronic pain states. The expression of NGF is high in injured and inflamed tissues, and activation of the NGF receptor tyrosine kinase trkA on nociceptive neurons triggers and potentiates pain signalling by multiple mechanisms. Inhibition of NGF function and signalling blocks pain sensation as effectively as cyclooxygenase inhibitors and opiates in rodent models of pain. Several pharmaceutical companies have active drug-discovery and development programs that are based on a variety of approaches to antagonise NGF, including NGF 'capture', blocking the binding of NGF to trkA and inhibiting trkA signalling. NGF antagonism is expected to be a highly effective therapeutic approach in many pain states, and to be free of the adverse effects of traditional analgesic drugs.

Extended efalizumab therapy improves chronic plaque psoriasis: results from a randomized phase III trial.

BACKGROUND: Efalizumab inhibits multiple T-cell-mediated processes. OBJECTIVE: To evaluate 12- and 24-week efalizumab therapy for psoriasis. METHODS: In this phase III, randomized, double-blind trial, 498 patients received subcutaneous 1 or 2 mg/kg/wk efalizumab or placebo for 12 weeks. Efalizumab-treated patients who achieved <75% Psoriasis Area and Severity Index improvement (PASI-75) were re-randomized to a second 12-week course of treatment. Results At week 12, 39% and 27% of efalizumab-treated patients (1 and 2 mg/kg, respectively) achieved PASI-75 (vs 2% placebo; P < .001, both dose groups). At week 24, an additional 20% of efalizumab-treated patients achieved PASI-75 (vs placebo 7%, P = .018). Efalizumab was well tolerated. CONCLUSION: Twelve-week efalizumab treatment resulted in significant improvement; extension of therapy to 24 weeks resulted in additional improvement in patients who initially had not achieved PASI-75. There were no significant changes in safety profile during weeks 13-24.

Pharmacokinetics and pharmacodynamics of multiple weekly subcutaneous efalizumab doses in patients with plaque psoriasis.

Efalizumab pharmacokinetics, pharmacodynamics, and efficacy were assessed after subcutaneous administration of 1.0 or 2.0 mg/kg/wk for 12 weeks with 12 weeks of follow-up in subjects with psoriasis. Steady-state serum concentrations were achieved by 4 and 8 weeks, respectively. C(max) was 12 and 31 microg/mL, occurring approximately 2 days after a SC dose. Serum trough levels were 9 and 24 microg/mL, and CL/F(ss) was 24 and 16 mL/kg/d. At both doses, CD11a expression on T lymphocytes was maximally down-modulated to approximately 20% of baseline, and CD11a binding sites were >95% saturated. The extent of this PD effect was less for other leukocytes. Leukocyte counts increased by approximately 40%, with the majority of this increase related to a significant but reversible increase in the lymphocyte population. Maximal pharmacodynamic effects were sustained at both dose levels through the course of treatment and were commensurate with improvements in psoriasis.

Safety of efalizumab in patients with moderate to severe chronic plaque psoriasis: review of clinical data. part II.

BACKGROUND: The efficacy and safety of efalizumab have been evaluated in multiple clinical trials. OBJECTIVE: The purpose of this review is to provide an overview of the safety profile of efalizumab during the clinical trials. METHODS: Twelve-week data from four placebo-controlled trials were pooled and analyzed. Data from patients receiving 13-60 weeks of efalizumab therapy were pooled to evaluate longer-term safety. RESULTS: The most common adverse events were mild to moderate, self-limiting, flu-like symptoms that were most frequent following the first two efalizumab doses; by the third dose the incidence was comparable to placebo. Serious adverse events were observed in 2.2% and 1.7% of efalizumab- and placebo-treated patients, respectively. Nonserious adverse events leading to withdrawal were infrequent and similar to placebo (2.8% vs 1.8%). There does not appear to be increased risk of end-organ toxicity, infection, or malignancy in efalizumab-treated patients. CONCLUSION: Efalizumab was well tolerated, with a favorable safety profile.

Clinical efficacy of efalizumab in patients with chronic plaque psoriasis: results from three randomized placebo-controlled Phase III trials: part I.

BACKGROUND: Effective psoriasis therapies are needed for long-term symptom control. OBJECTIVE: Assess efalizumab (Raptiva) efficacy in a large cohort of psoriasis patients. METHODS: Data from three Phase III, randomized, double-blind, parallel-group, placebo-controlled, multicenter studies were pooled. Patients (n = 1,651) with moderate to severe plaque psoriasis received 12 weeks of subcutaneous efalizumab 1 or 2 mg/kg/wk or placebo. RESULTS: All efficacy measures reached statistical significance within each of the individual studies (p < 0.001) and overall. More efalizumab-treated patients achieved > or = 75% and > or = 50% Psoriasis Area and Severity Index (PASI) improvement at week 12 than did placebo-treated patients (27.8% vs 3.8% [p < 0.001] and 56.1% vs 14.6% [p < 0.001], respectively). Significant PASI improvements occurred as early as week 2 (12.5% vs 7.9%, p =0.0001). Adverse events were generally mild to moderate. CONCLUSION: Efalizumab resulted in early and significant improvement for all efficacy endpoints and was well tolerated in patients with moderate to severe chronic plaque psoriasis.

Extended efalizumab therapy sustains efficacy without increasing toxicity in patients with moderate to severe chronic plaque psoriasis.

Agents that safely provide long-term control of psoriasis are needed. To determine the safety and efficacy of extended efalizumab therapy, 339 patients with moderate to severe chronic plaque psoriasis received 2 mg/kg subcutaneous (SC) efalizumab weekly for 12 weeks. At Week 12, 290 patients who achieved > or =50% Psoriasis Area and Severity Index (PASI-50) improvement or a static Physician's Global Assessment grading of "mild," "minimal," or "clear" entered maintenance treatment with weekly SC efalizumab. At Week 12, 82%, 41%, and 13% of 339 patients achieved a PASI-50, PASI-75, and PASI-90 response, respectively. At 15 months, 65%, 50%, and 25% of patients achieved a PASI-50, PASI-75, and PASI-90 response, respectively (intent-to-treat, n = 339). The incidence of adverse events did not increase over time, and no new common adverse events were reported. The majority of patients experienced sustained efficacy with no increase in toxicity. This study is planned to continue; patients will receive up to 36 months of continuous efalizumab.

Efalizumab for patients with moderate to severe plaque psoriasis: a randomized controlled trial.

CONTEXT: Because T-cell interactions are involved in the pathophysiology of psoriasis, therapy with a T-cell modulator may have beneficial effects on psoriasis severity and health-related quality of life (HRQL). OBJECTIVE: To assess the efficacy and safety of efalizumab, a T-cell modulator, in patients with plaque psoriasis. DESIGN, SETTING, AND PATIENTS: Phase 3 randomized, double-blind, parallel-group, placebo-controlled trial involving 556 adult patients with stable, moderate to severe plaque psoriasis and conducted at 30 study centers in the United States and Canada between January and July 2002. INTERVENTIONS: Patients were randomly assigned in a 2:1 ratio to receive 12 weekly doses of subcutaneous efalizumab, 1 mg/kg (n = 369), or placebo equivalent (n = 187). MAIN OUTCOME MEASURES: At least 75% improvement on the Psoriasis Area and Severity Index (PASI-75); improvement on the overall Dermatology Life Quality Index (DLQI), Itching Visual Analog Scale (VAS), and Psoriasis Symptom Assessment (PSA) at week 12 vs baseline. RESULTS: Efalizumab-treated patients experienced significantly greater improvement on all end points than placebo-treated patients. Twenty-seven percent of efalizumab-treated patients achieved PASI-75 vs 4% of the placebo group ( P<.001). Efalizumab-treated patients exhibited significantly greater mean percentage improvement than placebo-treated patients on the overall DLQI (47% vs 14%; P<.001), Itching VAS (38% vs -0.2%; P<.001), and PSA frequency and severity subscales (48% vs 18% and 47% vs 17%, respectively; P<.001 for both) at the first assessment point. Efalizumab was safe and well tolerated, with primarily mild to moderate adverse events. CONCLUSION: In this 12-week study, efalizumab resulted in significant improvements in clinical end points, including physician-assessed and dermatology-specific patient-reported HRQL measures, in patients with moderate to severe plaque psoriasis.