Hydrogels: from controlled release to pH-responsive drug delivery

Hydrogels are one of the upcoming classes of polymer-based controlled-release drug delivery systems. Besides exhibiting swelling-controlled drug release, hydrogels also show stimuli-responsive changes in their structural network and hence, the drug release. Because of large variations in physiological pH at various body sites in normal as well as pathological conditions, pH-responsive polymeric networks have been extensively studied. This review highlights the use of hydrogels (a class of polymeric systems) in controlled drug delivery, and their application in stimuli-responsive, especially pH-responsive, drug release.     

Death from actinomycosis

Death from actinomycosis, although unusual today, was devastating at one time. Although commonplace today, using antibiotics to save patients from death was unusual when penicillin was first introduced over 50 years ago.     

Development pharmaceutics of microbicide formulations. Part II: formulation,evaluation, and challenges

In recent years, AIDS and sexually transmitted diseases (STDs) have become a burgeoning problem and are spreading at an alarming rate. Microbicides are being developed as a new therapeutic category for prevention of transmission of sexually transmitted infections (STIs) and HIV. Many of the microbicide formulations (MF) may fail to elicit a protective response either because of a lack of efficacy or inadequate formulation. Manufacturing a stable, efficacious, safe, and optimal product is the main objective of formulation development programs. Preformulation parameters (PP), as discussed in Part I of this series, influence formulation development significantly and should be considered carefully before designing a formulation strategy. Initially, based on PP and market research, a target product profile (TPP) is generated, which defines product attributes that can be normally classified as "essential" and "desirable." A complex and dynamic process begins thereafter that takes into consideration myriad factors starting from selection of delivery system, selection of excipients, compatibility study, prototype composition, selection of process and optimization, stability testing, scale up, manufacturing under good manufacturing practices (GMP), and packaging development. Prototype formulations are evaluated for several performance characteristics (e.g., dispersion behavior, bioadhesion, retention, spreading, rheology). These compositions are also subjected to biologic evaluation by various in vitro and in vivo models. Such a well-planned, well-coordinated, and well-implemented formulation development program not only accelerates overall development but also minimizes failures in subsequent clinical development studies. The objective of this review is to highlight the importance of formulation science, outline the steps involved in this process, and explore how these can be exploited for achieving optimal MF.     

Addressing tobacco in managed care: a survey of dentists' knowledge,attitudes, and behaviors

OBJECTIVES: This study assessed the tobacco cessation knowledge, attitudes, and behaviors of dentists participating in a large managed care dental plan. METHODS: Participating dentists in 4 states were surveyed via mail. RESULTS: Dentists' perceived success in helping patients quit using tobacco was highly correlated with discussion of specific strategies for quitting, advice about the use of nicotine gum, and time spent counseling patients. Dentists who were confident about their smoking cessation knowledge frequently advised patients to quit and spent more time counseling patients about tobacco cessation. CONCLUSIONS: Tobacco cessation is not a routine part of dental practice. Knowledge, time spent counseling patients, and specific strategies for quitting were associated with dentists' perceptions of success.     

American Society of Clinical Oncology technology assessment on the use of aromatase inhibitors as adjuvant therapy for women with hormone receptor-positive breast cancer: status report 2002.

OBJECTIVE: To conduct an evidence-based technology assessment to determine whether the routine use of anastrozole or any of the aromatase inhibitors in the adjuvant breast cancer setting is appropriate for broad-based conventional use in clinical practice. POTENTIAL INTERVENTIONS: Anastrozole, letrozole, and exemestane. OUTCOMES: Outcomes of interest include breast cancer incidence, breast cancer-specific survival, overall survival, and net health benefit. EVIDENCE: A comprehensive, formal literature review was conducted for relevant topics and is detailed in the text. Testimony was collected from invited experts and interested parties. The American Society of Clinical Oncology (ASCO)-prescribed technology assessment procedure was followed. BENEFITS/HARMS: The ASCO panel recognizes that a woman and her physician's decision regarding adjuvant hormonal therapy is complex and will depend on the importance and weight attributed to information regarding both cancer and non-cancer-related risks and benefits. CONCLUSION: The panel was influenced by the compelling, extensive, and long-term data available on tamoxifen. Overall, the panel considers the results of the Arimidex (anastrozole) or Tamoxifen Alone or in Combination (ATAC) trial and the extensive supporting data to be very promising but insufficient to change the standard practice at this time (May 2002). A 5-year course of adjuvant tamoxifen remains the standard therapy for women with hormone receptor-positive breast cancer. The panel recommends that physicians discuss the available information with patients, and, in making a decision, acknowledge that treatment approaches can change over time. Individual health care providers and their patients will need to come to their own conclusions, with careful consideration of all of the available data. (Specific questions addressed by the panel are summarized in Appendix 3.) VALIDATION: The conclusions of the panel were endorsed by the ASCO Health Services Research Committee and the ASCO Board of Directors.     

A phase II study of paclitaxel plus carboplatin as first-line chemotherapy for women with metastatic breast carcinoma

BACKGROUND: This Phase II multicenter study evaluated the efficacy and toxicity of paclitaxel (200 mg/m(2) by 3-hour infusion) with carboplatin (area under the curve 6 mg/mL per minute) administered every 3 weeks as first-line therapy for women with metastatic breast carcinoma. METHODS: Eligible patients had measurable metastatic disease and an Eastern Cooperative Oncology Group performance status of 0-2. Prior adjuvant chemotherapy, including anthracycline-based therapy, was allowed, as was prior hormonal therapy as part of either adjuvant treatment or treatment for metastasis. Prior therapy with taxanes or platinum was not allowed. RESULTS: A total of 53 patients were enrolled in this study, with 50 patients evaluable for response and toxicity. The overall response rate was 62% (95% confidence interval ?CI, 48-75%); 16% of patients had complete responses and 46% had partial responses. The median time to progression was 7.3 months (95% CI, 5.9-12.9), and the 12-month survival estimate was 72% (95% CI, 61-86%). Therapy was generally well tolerated. Grade 3-4 neutropenia was the predominant toxicity, observed in 82% of patients, but there were no episodes of febrile neutropenia or sepsis. Hematopoietic growth factors were not routinely necessary. Grade 3 peripheral neuropathy occurred in 16% of patients. CONCLUSIONS: Paclitaxel (200 mg/m(2)) with carboplatin (area under the curve 6 mg/mL per minute) demonstrated substantial efficacy in patients with metastatic breast carcinoma, and the 12-month survival rate of 72% was encouraging. This therapy represents a viable option for patients with metastatic disease.