Treatment period

Although most appHcations of fixed bed have multiple adsorber beds to treat continuous streams, batch operation using a single adsorber bed is an alternative. For purification appHcations, where one vessel can contain enough adsorbent to provide treatment for days, weeks, or even months, the cost savings and simplicity often justify the inconvenience of stopping adsorption treatment periodically for a short regeneration. 

Treatment and dose, ppm Treatment period, d Control values and proportional responses, % Reference... 

Figures 2 and 3 illustrate the constant release of pilocarpiae over the seven day treatment period. An initial burst of dmg iato the eye is seen ia the first few hours. This is temporary and the system drops to the rated value ia approximately six hours. The total amount of dmg released ia this transitory period is less than that normally given ia pilocarpiae ophthalmic solutions. The ocular hypotensive effect of these devices is hiUy developed within 2 hours of placement ia the conjunctival sac, and the hypotensive response is maintained throughout the therapy. This system replaces the need for eyedrops apphed four times per day to control iatraocular pressure.

Name and description of the investigational product(s). A summary of findings from non-clinical sfudies and from clinioal trials that is relevant to the trial. Summary of the known and potential risks and benefits, if any, to human subjects. Description of and justification for the route of administration, dosage, dosage regimen, and treatment period(s). A statement that the trial will be conducted in compliance with the protocol, GCP and the applicable regulatory requirement(s). Description of the population to be studied. References to literature and data that are relevant to the trial, and that provide background for the trial... 

Reacetylated chitin gels were used to treat leg and decubitus ulcers in paraplegic subjects [309]. Selected preparative conditions permitted to obtain a self-sustaining gel useful for this use. The treatment periods were 63-182 days and complete healing was obtained. 

This product is also only available by prescription. The recommended treatment period is up to 24 weeks (McNeil Consumer Products 1997). Using the inhaler by puffing 80 deep inhalations over 20 minutes results in a systemic absorption through the buccal mucosa of 2 mg of nicotine, with maximal nicotine concentrations occurring 15 minutes after the end of inhalation. When the product is used as directed, the patient will likely use 6-16 inhalers per day. This form of NRT is relatively contraindicated in patients with asthma because, although most of the nicotine is absorbed through the buccal mucosa and it is not delivered to the lungs (McNeil Consumer Products 1997), nicotine by inhalation may produce bronchial constriction. 

A number of randomized chnical trials have demonstrated the efficacy of CBT for treating substance use disorders, compared with no-treatment control conditions (see Carroll 1996 for review). However, the superiority of CBT over other psychosocial treatments is not as clear. Although some studies have found CBT to be more effective than other treatments, others have found this method to be comparable to other treatment approaches (Carroll 1996). In Project MATCH, for instance, CBT, MET, and 12-step facihtation produced similar outcomes, with each therapy leading to substantial improvement in alcohol-related symptoms during the 12-week treatment period (Project MATCH Research Group 1997). 

FIGURE 7.3 CAST, 1ST and MAST—overview of overall effects of early aspirin treatment in acute ischemic stroke on clinical events during scheduled treatment periods. (From reference 19, with permission.)... 

The common method of treating rod-pumped wells is to periodically batch inhibitor into them. The treatment period for a given well is selected using empirical rules based on well production volumes. A successful and economic corrosion inhibition program must carefully control the inhibitor concentration in the well fluids. Environmental aspects and efficacious inhibitor usage necessitate the measurement of very low corrosion inhibitor concentrations. Inhibitor concentrations as low as one part per million are significant, thus... 

Inhaled corticosteroids are not equivalent on a milligram basis however, equivalent doses have been approximated (Table 11-3). Low to moderate doses have been shown to be safe and effective in all age groups. Although some effect is seen from inhaled corticosteroids within 12 hours, 2 weeks of therapy is necessary to see significant clinical effects, and longer treatment periods maybe necessary to see the full effect of these agents on airway inflammation and remodeling. 

Recommend a follow-up visit if signs and symptoms worsen at any time or do not improve within the defined treatment period. 

Treat behavioral and psychiatric issues as they arise. Consider the patient s choices of nonpharmacologic and pharmacologic options before recommending a treatment. Discontinue the pharmacologic treatments periodically to re-evaluate the need for continued treatment. 

Methotrexate has been used successfully with cyclosporine, either concurrently34 or in rotation. Rotational therapy is particularly effective since it minimizes the serious adverse effects of both agents hepatotoxidty from methotrexate and hypertension and nephrotoxicity from cyclosporine. Having an overlapping treatment period may not be necessary and patients have been successfully switched after a 1-week washout period.21,35 This is a very useful combination of systemic agents in the longterm management of this chronic disease. 

Preparation of seedlings for treatments with extract-amended nutrient solution was similar to that described for testing the effects of phenolic acids, except 40 plants were used per treatment and no replacement of the nutrient solution was made during the treatment period. Data collection procedures were modified in that only ab-axial leaf resistance was obtained and water potential was determined from four plants each day. Prior work established that abaxial resistance provided an adequate indicator of stomatal effects. The data were analyzed as described in experiments with pCA and FA. 

Their second study19 examined differences between boiled coffee and paper-filtered coffee for four weeks each with a two-week washout period in between treatment periods in 28 women and 13 men, 23 to 61 years old, with an average baseline total cholesterol of 5.5 mmol/L (210 mg/dL). Subjects were instructed to continue to drink their habitual amount of daily coffee, which ranged from 2 to 14 cups, with either boiled or drip coffee. With boiled coffee, both total cholesterol and LDL-C levels were significantly higher (0.32 mmol/L [12 mg/dL]) while HDL-C levels were modestly lower (0.07 mmol/L [3 mg/dL]). 

Diabetic Rats-Phase II. This protocol was similar to that in phase I except that 65 mg/kg STZ was employed, 54 HJ bovine insulin in the polyacid resin was utilized in each dose and the treatment period was for nine days. Groups of rats (four per group) were then sacrificed at 30,90,165 and 255 minutes after the last dosing. 

There are occasions when it is not possible to use a cross-over design in a bioequivalency determination. For example, if the half-life of the drug is very long, the required washout period between the two treatment periods may be several months. Obviously, it is quite impracticable to consider such a long washout period. Test subjects are unlikely to wait patiently for long periods of time, and thus if we tried to conduct a bioequivalency study with, say, a 3-month washout period, we would probably find that a significant number of our test subjects would not be available for the second dose. 

The slurry bioreactor developed by ECOVA Corporation65 showed a 93.4% reduction in PAHs over a 12-week treatment period with an initial 89.3% reduction in the first two weeks. 

These continuation trials tell a very different story from that told by relapse-prevention trials. They show that there is little difference between antidepressant and placebo even when the clinical trial is extended over a longer period of time. Across the eight continuation trials that have been published, 79 per cent of patients on placebo and 93 per cent of patients on active medication remained well throughout the treatment period. In these long-term studies, placebo treatment was 95 per cent as effective as drug treatment. The authors of a meta-analysis of these trials concluded that the widely held - and probably erroneous - belief that the placebo response in depression is short-lived appears to be based largely on intuition and perhaps wishful thinking .17... 

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