Pharmacogenomics, informatics, and individual drug therapy in psychiatry: past, present and future

The modern era of psychopharmacology began in the 10 year period from the late 1940s to the late 1950s. During this period, the first antidepressants, antipsychotics, anxiolytics and mood stabilizers were all discovered. In the 1960s, the pharmacology of these drugs was elucidated and theories about the mechanisms of action proposed. In the 1970s and 1980s, new, more selective compounds were developed based on improved structure-activity relationships derived from in vitro receptor binding studies and animal models. These compounds entered clinical testing in the 1980s and began to be marketed in the late 1980s and 1990s. All of these agents were approved to treat psychiatric syndromes which are conditions defined by a cluster of signs and symptoms. None of these agents was developed based on an understanding of the pathophysiology of the illnesses being treated. None of these agents are curative and virtually all have limited clinical efficacy. In the earliest days of the modern era, there were few drugs available to combine and many had such broad actions that they were often marginally tolerated or unsafe when used in combination (tricyclic antidepressants and monoamine oxidase inhibitors). With the advent of more medications, the frequency and extent of polypharmacy has exploded. In addition to simply having more drugs from which to select with different pharmacological profiles, many newer medications are also more selective in their pharmacological actions and thus are often better tolerated and safer when used in combination. In addition, there is the concern that the trade-off for more selective pharmacology may have been better tolerability at the expense of reduced efficacy, which clinicians then compensate for by using more medications in combination. For all of the above reasons, polypsychopharmacology has been present from the beginning of the modern era of psychopharmacotherapy and continues to be the rule rather than the exception. In fact, the frequency and the complexity of such polypsychopharmacology are both enormous and increasing. The percentage of patients being discharged from the Biological Branch of the National Institute of Mental Health on more than three psychiatric medications increased more than ten times between 1974-79, and 1990-95. The majority of patients seen in the Veterans Administration Medical System in the United States are on unique combinations of medications and the frequency and complexity of such polypharmacotherapy is increased in patients on psychiatric medications. Throughout the modern era, there have been attempts to determine whether there are populations of patients selectively responsible to specific agents (e.g. serotonin versus norepinephrine reuptake inhibitors). However, no compelling data have so far emerged. Instead, clinicians generally resort to combining drugs on the basis of symptoms such as psychosis and depression or anxiety and depression. Science has primarily informed the clinician about safety concerns rather than efficacy concerns when using such combinations. That will change in the future with a better understanding of the pathophysiology of psychiatric illnesses which in turn will lead to improved therapies and the potential for more rationally derived combination treatments.

Update in methodology and conduct of cancer clinical trials

Many interesting changes are regularly brought into the methodology of cancer clinical trials. This position paper focuses on three topics which are felt to appear as recurrent problems which deserve more attention from the scientific community. RECIST guidelines were published five years ago and have since then been largely implemented and used in clinical trials. Although the criteria were initially designed for screening phase II trials they have been used also in most phase III studies aiming at determining the efficacy of new treatments. Problems have been identified some of which require further clarifications and others deserve further research which is being undertaken. Overall RECIST is well accepted and a revised version is being considered for 2007. Interim analysis is also an important issue revealed recently through many large adjuvant or advanced trials being prematurely discontinued at the time of an interim analysis. In most instances trials were stopped because of evidence of superiority of the investigational treatment over the standard treatment. Premature discontinuation of trial poses a number of challenges addressed in this paper. Finally, the consequences of the implementation of the EU clinical trial directive are being discussed. The conclusions are without equivoque. There is much less academic research conducted in Europe, there is a lot of discrepancy and inconsistency in the implementation of the directive across member states and there is no apparent direct benefit for the patients.

The future of gene therapy in the UK

Gene therapy encompasses a spectrum of therapeutic strategies, ranging from the compelling concept of using wild type copies of genes to correct the root cause of recessive genetic disorders through to using genes to mediate powerful and selective toxicity to cancer cells. Inspirational for the general public as well as the bioscience community, gene therapy has been grabbing the headlines--for good and bad reasons--regularly for the past 15 years. In this personal appraisal, Professor Len Seymour assesses the progress of gene therapy in the UK and what it might deliver in the foreseeable future.

[Lung cancer]

Although various benign and malignant tumors can occur in the bronchi and lungs, lung cancer is by far the most common tumor and the leading cause of tumor death worldwide. For therapeutic reasons lung cancer is classified currently as small cell (SCLC) or non small cell lung cancer (NSCLC). The main cause is smoking. There are no specific symptoms that enable early detection. Staging is according to the international TNM-system. As the results of therapy to date are disappointing and many questions remain unsolved, as many patients as possible should be included in further prospective trials. In SCLC polychemotherapy is mandatory; in local tumor stages radiotherapy should be combined early on with chemotherapy, and in cases of complete remission, prophylactic cranial irradiation is indicated. In operable stages of NSCLC adjuvant chemotherapy demonstrates a survival benefit. In locally advanced NSCLC, radiochemotherapy is now the standard of care. Advanced stages require chemotherapy usually with two drugs, second-line chemotherapy is indicated in cases of relapse.

[Targeted therapy in the treatment of solid tumors and in hematology-oncology. Advances and disappointments]

The development and clinical introduction of targeted therapies has resulted in significant progress for the treatment of malignant diseases. These forms of therapy supplement traditional methods of chemotherapy, radiation, and surgery. As new therapies increase the complexity of therapeutic options in oncology, the treatment costs steadily climb as well. Parameters need to be identified which will predict a response to new substances, and this effort is the subject of ongoing studies.

Issues in neuroprotection clinical trials in Parkinson's disease

Despite advances in understanding the pathogenesis of Parkinson's disease (PD), treatments that favorably influence the course of illness have remained elusive. In order to identify potentially neuroprotective interventions, improved clinical trial designs are needed. Researchers have to carefully consider what type of PD patients, how to measure the impact of putative neuroprotective agents, how to choose which interventions to study and what sequence of clinical trial designs is most appropriate. The possible use of futility studies to rapidly identify strongly ineffective agents and the use of delayed start designs to identify disease modifying interventions may both be important advances. Improved clinical trial design along with continued new insights into PD pathogenesis will likely lead to the identification of agents which can favorably influence the course of this disease.

Towards therapeutic vaccines for colorectal carcinoma: a review of clinical trials

Colorectal carcinoma is a leading cause of cancer-related mortality. Despite the introduction of new cytotoxic drugs, improved surgical and radiotherapeutic techniques, a large proportion of colorectal carcinomas remain incurable. New targeted therapeutic strategies, including immunotherapy, are being explored as complementary treatments. Recent advances in immunology and molecular biology have opened new avenues for the clinical testing of rationally designed vaccination strategies against cancer. The present report reviews the results of therapeutic vaccine trials in colorectal carcinoma, published mainly in the past 6 years. Tumor-associated antigens (self-antigens) have been targeted by therapeutic vaccination in more than 2000 colorectal carcinoma patients. The results demonstrate that tumor antigen-specific immune responses are reproducibly induced; that is, tolerance can be reversed, without the induction of serious adverse events or autoimmune disorders. No long-term autoimmune side effects have been observed after a minimum follow-up of 4 years in over 700 patients. Over 1300 colorectal carcinoma patients with minimal residual disease have been enrolled in randomized controlled Phase II/III trials using autologous tumor cell vaccines. A significantly improved overall survival was noted for Stages I-IV colorectal carcinoma patients utilizing Newcastle-disease virus as an adjuvant. Autologous tumor cells mixed with bacillus Calmette-Guerin (BCG) were of significant clinical benefit for patients with Stage II colon cancer. Results of randomized controlled trials targeting Ep-CAM have shown clinical benefit in subgroups of patients. Several new generation vaccines have demonstrated excellent safety profile and immunogenicity. Some studies have also demonstrated a statistically significant correlation between the induced immune response and prolonged overall survival, which should be confirmed in enlarged trials. Although it is unlikely that active specific immunotherapy will provide a standard complementary therapeutic approach for colorectal carcinoma in the near future, the results so far are encouraging. Randomized controlled vaccine trials targeting molecularly defined tumor antigens are warranted, particularly in colon carcinoma with minimal residual disease.

MRI-guided focused ultrasound: methodology and applications

Focused ultrasound is very well suited for inducing noninvasive local hyperthermia. Since magnetic resonance imaging (MRI) may be employed to obtain real-time temperature maps noninvasively the combination of these two technologies offers great advantages specifically aimed toward oncological studies. Real-time identification of the target region and accurate control of the temperature evolution during the treatment has now become possible. Thermal ablation of pathological tissue, local drug delivery using thermosensitive micro-carriers and controlled transgene expression using thermosensitive promoters have recently been demonstrated with this unique technology. Based on these experiments combined focused ultrasound and MRI thermometry holds promise for future oncological diagnostics and treatment. In this paper, we review some of the recent methodological developments as well as experimental and first clinical studies using this approach.

Proteomics in clinical trials and practice: present uses and future promise

The study of clinical proteomics is a promising new field that has the potential to have many applications, including the identification of biomarkers and monitoring of disease, especially in the field of oncology. Expression proteomics evaluates the cellular production of proteins encoded by a particular gene and exploits the differential expression and post-translational modifications of proteins between healthy and diseased states. These biomarkers may be applied towards early diagnosis, prognosis, and prediction of response to therapy. Functional proteomics seeks to decipher protein-protein interactions and biochemical pathways involved in disease biology and targeted by newer molecular therapeutics. Advanced spectrometry technologies and new protein array formats have improved these analyses and are now being applied prospectively in clinical trials. Further advancement of proteomics technology could usher in an era of personalized molecular medicine, where diseases are diagnosed at earlier stages and where therapies are more effective because they are tailored to the protein expression of a patient's malignancy.

What is new about idiopathic intracranial hypertension? An updated review of mechanism and treatment

Idiopathic intracranial hypertension (IIH) is the syndrome of raised intracranial pressure without clinical, laboratory or radiological evidence of intracranial pathology. IIH is a relatively rare disease but rapidly increasing incidence is reported due to a global increasing incidence of obesity. Disease course is generally said to be self-limiting within a few months. However, some patients experience a disabling condition of chronic severe headache and visual disturbances for years that limit their capacity to work. Permanent visual defects are serious and not infrequent complications. The pathophysiology of IIH is still not fully understood. Advances in neuroimaging techniques have facilitated the exclusion of associated conditions that may mimic IIH. No causal treatment is yet known for IIH and existing treatment is symptomatic and rarely sufficient. The aim of this review is to provide an updated overview of this potentially disabling disease which may show a future escalating incidence due to obesity. Theories of pathogenesis, diagnostic criteria and treatment strategies are discussed.

Clinical trials aimed at detecting neuroprotection in Parkinson's disease

Potential neuroprotective therapies for Parkinson's disease (PD) are being identified in the laboratory and evaluated in the clinic in an effort to improve long-term outcomes for patients. Several clinical trial designs and methodologies have been used in an attempt to identify neuroprotective effects of medications. Such studies have evaluated (a) time to onset of a clinical milestone of disease progression, (b) progression of clinical symptoms from untreated baseline to an untreated endpoint obtained after wash-out of study intervention, (c) progression of clinical symptoms in early PD, (d) change in imaging markers over time, and (e) a combination of clinical (wash-out) and imaging markers. None of these approaches has yet provided a definitive means to evaluate neuroprotection. Clinical outcomes can be confounded by symptomatic effects of treatments, and imaging markers can be affected by pharmacologic or pharmodynamic changes resulting from treatment. Better methods of assessing putative neuroprotection in PD are needed.

Rationale for considering that propargylamines might be neuroprotective in Parkinson's disease

A neuroprotective therapy that slows or stops disease progression is the major unmet medical need in Parkinson's disease (PD). Current evidence indicates that cell death in PD occurs, at least in part, by way of a signal-mediated apoptotic process. This raises the possibility that anti-apoptotic agents might be neuroprotective in PD. Propargylamines have been demonstrated to be potent anti-apoptotic agents in both in vitro and in vivo studies, presumably by maintaining glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as a dimer and thereby preventing its nuclear translocation where it blocks upregulation of anti-apoptotic proteins. Selegiline is a monamine oxidase type B (MAO-B) inhibitor that incorporates a propargyl ring within its molecular structure. It was shown to delay the need for symptomatic therapy in untreated PD patients in the DATATOP study, but interpretation is confounded by its symptomatic effects. Rasagiline is another MAO-B inhibitor that contains a propargyl ring and has protective effects in laboratory models. A clinical trial utilizing a delayed start design demonstrated that patients initiated on rasagiline at baseline are improved at one year in comparison to patients initiated on placebo and switched to rasagiline at 6 months even though both groups were on the same treatment for the last 6 months of the study. These results argue against the benefit being due to a symptomatic effect and are consistent with rasagiline having a protective effect.

Quality of Japanese clinical trials estimated from good clinical practice audit findings

To describe qualitatively recent changes in the Japanese clinical trial environments, we compared the results of the Good Clinical Practice (GCP) audits conducted from April 1997 to March 2000 (FY1997 to FY1999) with those from April 2002 to March 2003 (FY2002). In addition, the audit results were compared between the United States and Japan. The audit findings in the former period were based on the official audits by the Organization for Pharmaceutical Safety and Research (OPSR) that covered 331 hospitals and 775 trials. The audits by the OPSR in the latter period targeted 136 hospitals and 226 trials. The total number of deficiencies detected in the Good Clinical Practice audits in the former 3-year period (FY1997 to FY1999) was 1529, and the number in the single year (FY2002) was 1627. The total number of deficiencies detected and reported was about 3-fold on an annual basis between the periods. By category of deficiencies, there were 2 remarkable changes in the OPSR's audit findings between FY1997-FY1999 and FY2002. One was an increase in the proportion of protocol deviations from 14.7% (225/1529) in FY1997-FY1999 to 48.2% (785/1627) in FY2002, and the other was a decrease in the proportion of case report form-related deficiencies from 43.6% (666/1529) to 16.0% (260/1627). The high prevalence of protocol nonadherence and the relatively few findings of informed consent errors were important characteristics of Japanese trials inferred from the audit result reported by the OPSR in FY2002. In the United States, relatively high proportions of protocol nonadherence and informed consent errors were observed in the audit finding reported in 1997. Although the audit results for clinical trials between the United States and Japan are not strictly comparable, our results suggest that protocol deviations are a compelling issue for quality improvement in the conduct of clinical trials for the 2 regions.

[Structure, use, and risks of biomaterial repositories of embryonal tumors]

Availability of statistically sufficient numbers of tumor samples and other biomaterials in high quality together with corresponding clinical data is crucial for biomedical research. Tumor repositories from individual scientists are mostly not sufficient to satisfy these criteria, especially since pediatric tumors are rare. In 2000 three centralized tumor repositories (neuroblastoma in Cologne, nephroblastoma in Würzburg, hepatoblastoma, brain tumors in Bonn) have been established by the "German Competence Net Pediatric Oncology und Hematology". The aim was to collect biomaterial including tumor samples, normal tissue, and blood in high quality for research and diagnostic purposes at a central institution. Informed consent of the parents or patients is a prerequisite for scientific use of the samples and is requested by the therapy trial. The samples are collected according to accepted standards and shipped in the specially designed Tumorbox. The tumor repository organizes the distribution of the samples to the cooperating diagnostic laboratories. The number of collected tumor samples has increased over the years. In 2000, samples from 200 patients were collected while the patient number increased to 321 in 2005. Over the years the tumor repositories collected more than 7,150 samples (fresh frozen tumor, fresh frozen normal tissue, and blood). Through links with clinical trial databases the samples can be connected with clinical data. 12 of 14 applications for tumor material to be used in specific scientific projects have been approved by an independent supervisory board. The establishment of central tumor repositories represents a major step for biomedical research activities and quality control in pediatric oncology.

[Renal cancer study activities in Germany. Drug therapy]

Drug therapy of advanced renal cell carcinoma underwent rapid changes. Monotherapeutic, placebo-controlled protocols -- and more recently combinations of different targeted drugs -- dominated the global clinical studies in the past 2 years. The preliminary results are almost encouraging and international investigators, supported by the pharmaceutical industry, were most successful in enrolling patients quickly. The present article reviews the recent German drug study activities and indicates potential future projects.