2019, Touro College, Hassan's review: "Purchase online Tamoxifen cheap - Best Tamoxifen OTC".
Data from head-to-head trials are limited to one short-term head-to-head trial in patients with genotype 1 infection generic tamoxifen 20 mg with amex. Estimates from indirect analysis of SVR for specific HCV genotypes and in HIV co-infected patients are too imprecise to make reliable judgments about comparative efficacy purchase tamoxifen 20 mg without a prescription. There are almost no data to determine whether comparative efficacy or safety varies according to race tamoxifen 20mg visa, gender, age, presence of obesity, severity of baseline disease, or other co-morbid conditions. Race, gender, or age 40, 44, 48, 62 95, 106, 127 Some studies have found older age and black race to be associated with poorer response to dual therapy with pegylated interferon. However, we found no studies evaluating whether comparative effectiveness and safety of dual therapy with pegylated interferon alfa-2a versus dual therapy with pegylated interferon alfa-2b varies according to race, 72 gender, or age. In all trials except for one, the majority of enrollees were male. Average age in 35 74 the trials ranged from 34 years to 54 years, with the exception of a trial of thalassemic 53 patients with a mean age of 20 years. Race was reported in four of 19 other trials comparing dual therapy with pegylated interferon to either dual therapy 44, 48, 57, 73 with non-pegylated interferon or to pegylated interferon monotherapy. The proportion of black enrollees ranged from 5% to 33% in these trials. One small subgroup analysis (N=32) Pegylated interferons for hepatitis C Page 35 of 65 Final Report Drug Effectiveness Review Project 48 of Mexican patients enrolled in a large, international multicenter trial reported SVR rates of 50% (7/14) for dual therapy with pegylated interferon alfa-2a versus 33% (4/12) for dual therapy 38 with non-pegylated interferon alfa-2b. Other trials have been conducted in Saudi Arabia or 34, 46, 47, 59 Egypt and in Asia. Two non-randomized studies reported adverse events rates in black 95, 106 patients compared to white patients. However, no study directly compared efficacy or safety of dual therapy with pegylated interferon alfa-2a versus dual therapy with pegylated interferon alfa-2b by ethnic or racial subgroups. HCV genotype Several trials of dual therapy with pegylated interferon have found HCV genotype 1 43, 48, 58, 59, 61, 73 independently associated with a lower likelihood of SVR. One small (N=36), short-term, head-to-head trial directly compared dual therapy with pegylated interferon alfa-2a to 71 dual therapy with pegylated interferon alfa-2b in patients with HCV genotype 1 infection. Because of it’s small size, short duration of follow-up, and non-standard dosing (4 weeks of monotherapy followed by 4 weeks of dual therapy), it is of very limited value for judging comparative efficacy (see Key Questions 1 and 2). The large (N=2,880) IDEAL study is a head- 129 to-head trial in patients with HCV genotype 1 infection, but results are not yet available. Twelve trials provide indirect evidence on efficacy of dual therapy with pegylated interferon alfa-2a versus dual therapy with pegylated interferon alfa-2b. Eight trials of dual therapy with pegylated interferon versus dual therapy with non-pegylated interferon restricted 70, 74 enrollment to genotype 1 patients or reported subgroup results for patients with genotype 1 44, 45, 48, 59, 63, 73 infection. Four trials reported results for the subgroup of patients with either 43, 45, 58, 61 genotype 1 or 4 infection. Six trials reported results for patients infected with HCV 45, 48, 58, 61, 63, 73 genotype 2 or 3. Three trials reported SVR in patients with genotype 1 or genotypes 1 or 4 randomized to dual therapy with pegylated interferon versus pegylated 42, 48, 56 interferon monotherapy. There is insufficient evidence from pooled analyses to conclude that dual therapy with one pegylated interferon is superior to the other for HCV genotypes 1, 2, or 3 infection. Estimates of relative risk for SVR on dual therapy with pegylated interferon alfa-2a versus dual therapy with non-pegylated interferon and for dual therapy with pegylated interferon alfa-2b versus non-pegylated interferon were imprecise (particularly for trials of dual therapy with pegylated interferon alfa-2a), with overlapping confidence intervals (Table 11). Pooled analyses on sustained virologic response rates for genotypes 1, 2, and 3 Genotype Number of Relative risk Number of Relative risk trials for SVR (95% trials for SVR CI) Trials of dual therapy with Trials of dual therapy with pegylated interferon alfa-2a vs. HCV genotype 4 is far more common in Egypt, Saudi Arabia, and other North African Countries (up to two-thirds of infected patients) than in North America and 48, 63 Europe (less than 4% of patients in the two largest trials ). The systematic review included 48, 63 subgroup data from the two largest published trials and data from four other trials of patients with HCV genotype 4 infection published as conference abstracts (one trial since published as a 34 journal article). All of the trials compared dual therapy with pegylated interferon to dual therapy with non-pegylated interferon (three trials of pegylated interferon alfa-2a and three pegylated interferon alfa-2b). Compared to dual therapy with non-pegylated interferon, the systematic review found dual therapy with pegylated interferon alfa-2a significantly superior for achieving an SVR (RR 2. However, all of the trials of dual therapy with pegylated interferon alfa-2b used lower, non-weight based doses of ribavirin and two of the three trials did not use FDA-approved body-weight based doses of pegylated interferon. In addition, conclusions about relative efficacy from this data are likely to be misleading, as confidence intervals overlap for the two dual pegylated interferon regimens, and no formal indirect analysis was performed. We re-analyzed the data from the systematic review 45, 46 with additional data from two new trials of patients with HCV genotype 4 infection. Our indirect analysis shows no significant differences between pegylated interferon regimens on indirect analysis, with very wide confidence intervals (Table 12). Direct and indirect analyses on sustained virologic response rates for dual therapy with pegylated interferon Comparison Number of trials Relative risk for SVR (95% CI) Direct analysis Dual therapy with pegylated interferon alfa-2a versus 3 2. Analyses of the association between less severe baseline histologic findings and greater response to dual therapy with pegylated interferon are less consistent, with 40, 43, 44, 46 some trials showing no association after controlling for other factors. We identified no trials evaluating comparative effectiveness or safety of dual therapy with pegylated interferon alfa-2a versus dual therapy with pegylated interferon alfa-2b in patients with higher viral loads, more severe fibrosis or inflammation, or other markers of more severe baseline HCV disease. Pegylated interferons for hepatitis C Page 37 of 65 Final Report Drug Effectiveness Review Project Obese patients 48 Subgroup analyses of three trials found dual therapy with pegylated interferon alfa-2a 42, 63 and alfa-2b less effective at achieving an SVR in patients over 75 to 80 kg, compared to those below 75 to 80 kg. A potential advantage of pegylated interferon alfa-2b is that it is normally dosed according to weight (compared to uniform dosing for pegylated interferon alfa- 2a), which could theoretically help insure adequate drug levels in more obese patients. However, no trials have evaluated whether dual therapy with pegylated interferon alfa-2b is superior to dual therapy with pegylated interferon alfa-2a in obese patients, or whether weight-based versus standardized dosing is more effective in such patients. HIV co-infection HCV infection is present in approximately 30% of HIV-infected persons. We identified no head-to-head trial comparing dual therapy with pegylated interferon alfa-2a to dual therapy with pegylated interferon alfa-2b in HIV co-infected patients. We also found insufficient indirect evidence to determine if dual therapy with interferon alfa-2a differs from dual therapy 35, 44, 73 with interferon alfa-2b for efficacy or safety. Three trials compared pegylated interferon 43, 45, alfa-2a versus dual therapy with non-pegylated interferon alfa-2a or alfa-2b, and four trials 58, 68 compared pegylated interferon alfa-2b versus dual therapy with non-pegylated interferon alfa-2b in HIV co-infected patients. Pooled rates of sustained virologic response were 3. However, the latter analysis included the only trial to report lower rates of SVR on dual therapy with 68 pegylated interferon compared to dual therapy with non-pegylated interferon. This was the only non-randomized trial and was rated poor-quality. Excluding this trial, the relative risk for SVR was 1. Rates of SBR were only reported in one trial of HIV co- 58 infected patients. Risk of withdrawal due to adverse events were similar in three trials of dual therapy with pegylated interferon alfa-2a versus dual therapy with non-pegylated interferon alfa- 2a (RR 0. We did not perform indirect analysis because of overlapping confidence intervals and small numbers of trials. Other co-morbid conditions There is no evidence to evaluate comparative efficacy or safety of dual therapy with pegylated interferon alfa-2a versus dual therapy with pegylated interferon alfa-2b in patients with severe psychiatric illness or decompensated cirrhosis. Such patients were excluded from the trials and no observational studies were designed to evaluate these patient populations. Some randomized trials and observational studies included patient populations not 53 represented well in clinical trials, such as patients with thalassemia, patients on 131 83, 102 hemodialysis, patients with mixed cryoglobulinemia, and patients on methadone 101 maintenance. However, there was no evidence of clear difference in estimates of efficacy or safety from these studies compared to efficacy or safety of dual therapy with pegylated interferon in general. Pegylated interferons for hepatitis C Page 38 of 65 Final Report Drug Effectiveness Review Project SUMMARY AND DISCUSSION Results of this evidence review are summarized in Table 13. Summary of the evidence by key question Key Question Quality of the Conclusion Evidence 1. What is the comparative Fair to poor All trials are efficacy studies. Evidence is insufficient to effectiveness of regimens of judge comparative efficacy. Head-to-head trial data are peginterferon alfa-2a plus ribavirin sparse (two trials), short-term (8 to 12 weeks), clinically versus peginterferon alfa-2b plus diverse, and had methodological flaws.
As a rule of thumb buy tamoxifen 20 mg, ART should be changed quickly with insufficient viral suppres- sion and/or a rise in plasma viremia discount tamoxifen 20 mg line, as otherwise future options could be limited buy 20mg tamoxifen mastercard. One speaks of insufficient viral suppression or virologic failure if the viral load is repeatedly above the level of detection. A switch is not recommended with tempo- rary viremia (blips – more on this topic in the chapter Principles of Therapy). Tenofovir, abacavir, 3TC, FTC and ddI lose their efficacy in the presence of the K65R mutation, which is often selected by tenofovir-containing triple-nuke therapies. Viral replication with insufficient plasma levels is the best breeding ground for resistance. Therefore, it is recommended to act fast if a clear virologic failure occurs. The longer one waits, the more compli- cated it becomes. An insufficient viral suppression means, as stated before, a repeated viral load above 50 copies/ml. Some clinicians tolerate levels of up to 500 or even 1000 copies/ml for months. We believe such hesitation is not justified in most cases when patients have good options and good adherence. A patient’s frequent asser- tions of not having symptoms should not count too much, either. Obviously, such thoughts do not always play a role in clinical reality. In an analysis in Great Britain 34% out of 694 patients remained on a virologically unsuccessful combination for over 6 months. Factors associated with an early switch were low CD4 T cells, a high viral load and older age (Lee 2008). To date, only a few randomized trials have investigated strategies in patients in whom several ART combinations have failed: either the patients change immediately or when the viral load reaches a certain level (early versus deferred switch). The preliminary results of some small randomized studies indicate that even in such cases one can wait a short time (Nasta 2006, Tenorio 2009). It seems difficult to recruit physicians and patients to participate in such strategy trials. When to switch 211 Arguments for a rapid switch Arguments for a later switch in the case of virologic failure in the case of virologic failure The virus becomes incapable of generating New therapies bear the risk of new toxicities/ more resistance intolerance, which can lead to a termination of therapy Options are maintained Most patients are immunologically stable for a long time with low viremia (clinically) The switch is more successful with Replication fitness is reduced on failing treatment less resistance The lower the viral load at time of switch, Resistance testing is often not possible with low the better the response to the new therapy viral load, even though they are there, so you may switch “blindly” The following regimens do not have It is sometimes difficult to explain to the patient to be as complex as the present one – why change of a well-tolerated and simple some things can be simplified (QD, no more regimen is necessary d4T/ddI, etc. In the prospective Johns Hopkins Cohort there was no association between a deferral of ART modification and mortality in the course of treatment in patients on a PI showing virologic failure (Petersen 2008). This is why in the TITAN Study, the number of acquired PI mutations had no effect on the success of darunavir/r, although it did play a role for lopinavir/r (De Meyer 2008). In cases of clinical treatment failure (disease progression) or immunological failure (stagnation or decrease in the level of CD4 T cells) where the viral load remains below 50 copies/ml, the value of a change in therapy is unclear. Some combinations such as TDF+ddI are clearly unfavorable for immunological reconstitution (Negredo 2004). This may also be the case for AZT-containing regimens; such combinations should be changed. It is important that when virologic failure occurs, the individual situation of the patient is carefully analyzed. In particular, several questions need to be addressed: What are the reasons for the measurable viral load? A viral load above 50 copies/ml does not necessarily mean that resistance mutations have developed. A frequent cause may be a blip (see section on Goals and Principles of ART). These transient and, almost always, small increases in viral load usually have no relevance. However, a measurable viral load may be due to treatment failure. It may indicate insufficient plasma drug levels (measure these if possible). This may be due to drug malabsorp- tion, drug interactions or simply insufficient dosing (e. Any difficulties related to the regimen should be openly addressed. The risks of resistance development as a result of non-compliance should be reiter- ated. If plasma levels are sufficient and viral load remains detectable (monitor blips at short intervals – within a few weeks), treatment should be changed as soon as possible. NNRTI regimens are extremely sen- sitive, and cross-resistance can develop particularly rapidly for the whole class. A prompt change in therapy is more vital than with the other drug classes. Delaying 212 ART this by even a few days or weeks may be too long. Rapid development of resistance can also be expected with 3TC/FTC and probably with the integrase inhibitor ralte- gravir. A PI-containing regimen without an NNRTI may allow a little more time, but the credo still applies. The higher the viral load at the time of modification, the lower the chance of success. What options does the patient have, and what are the consequences of the change in therapy? The more options that remain available the sooner they should be utilized. Therapy can sometimes be intensified quite easily (e. In such cases, the decision to change or intensify a regimen is less difficult. On the other hand, it may be advisable in certain circumstances to con- tinue therapy in a patient, even if the plasma viremia is not completely suppressed. Often, the viral load does not rise above the baseline value, and the CD4 T cells remain stable or even increase. Resistance to nucleoside analogs are to be expected, so NNRTIs and PIs can be saved by waiting. Even when multiple resistance mutations are already present, one is probably able to wait (see above). Especially in patients with adherence problems, it does not make sense to run through new drug classes. Adherence will not automatically be better with newer regimens. One should talk with the patient, find out what needs to be made better, and clarify if they are really ready for intensification or modification of therapy. Virologic failure: to be considered before changing therapy • How resistance-sensitive is the present therapy? NNRTIs, 3TC/FTC, raltegravir, elvitegravir: rapid development of resistance, change quickly • The lower the viral load, the greater the prospect of success with a change • Are you sure it is virologic failure and not a temporary blip? Whether a gastric stimulant prescribed by the family doctor (i. How to Switch ART CHRISTIAN HOFFMANN Changing a regimen that is successful but intolerable due to side effects is usually easy. The suspected drug is replaced with another drug of the same class. It becomes more difficult if alternate drugs are contraindicated because of potential toxicity or if resistance mutations to these drugs are suspected. This is particularly true in subjects with a treatment history of 15 years or longer, who probably harbor multi-resistant viruses. Even physicians with lots of experience in treatment should discuss these complex individual cases with their colleagues.
The most important clinical findings are depressed or absent ankle reflexes discount tamoxifen 20mg mastercard, an elevated vibration threshold at toes and ankles and a decreased sensitivity to pain and temperature in a stocking distribution purchase 20 mg tamoxifen otc, whereas proprioception is usually normal cheap tamoxifen 20mg visa. Weakness and atrophy of intrinsic foot muscles are mild and are not features of the disease. Involvement of the upper legs and trunk, significant weakness of leg muscles or decreasing proprioception are not typical for DSSP and should raise suspicion of other disorders, for instance a conjoined myelopathy. Loss and dysfunction of small sympathetic and parasympathetic nerve fibers are essential features of the disease and may cause postural hypotension, erectile dysfunction, gastroparesis and alter- ations of skin or nails in many DSSP patients. Table 2: Clinical features of distal symmetrical sensory polyneuropathy Numbness, pain, dysesthesia and paresthesia in the feet and lower legs Decreased or absent deep ankle tendon reflexes Decreased or absent vibratory senses of the toes and ankles No or only minimal motor dysfunction No or only minimal involvement of the hands and arms Slowly progressive course Electrodiagnostic studies with features of axonal nerve damage Autonomic dysfunction: orthostatic hypotension, erectile dysfunction Medication-related toxic neuropathy A distal symmetrical sensory peripheral neuropathy occurs in about 10–30% of patients treated with ddI, d4T (and formerly, ddC). It is indistinguishable from HIV- induced DSSP on clinical examination or in electrodiagnostic studies. The only difference is in the exposure to neurotoxic nucleoside antiretroviral medication. Brew (2003) found an elevation of serum lactate in over 90% of patients with d4T-related neuropathies. NRTI neuropathy develops after a mean of 12–24 weeks of treatment. After with- drawal, there can be a temporary worsening for 2–4 weeks and improvement usually begins after 6-12 weeks. In several cases the restitution remains incomplete. In these cases there may have been an additional pre-existent damage to the peripheral nerves Neuromuscular Diseases 641 due to HIV infection itself. Subclinical disturbance of peripheral nerve function con- firmed by pathological findings in electrodiagnostic studies elevates the risk of devel- oping NRTI-related neuropathy. PIs seem to have a very low additional neurotoxicity. In combination with d4T, ddI or ddC they seem to be an additional risk factor for neuropathy (Ellis 2008, Evans 2001). The instruction leaflets of many PIs list peripheral neuropathy as a possible side effect, because neuropathic symptoms were slightly more often reported in the PI arms of clinical trials. In combination with ddI, d4T and ddC, PIs seem to be a risk factor for neuropathy on their own (Ellis 2008, Evans 2011). But there are no reports of cases of neuropathy that developed while on PI treatment that resolved after withdrawal. In clinical experience, the risk of PI-induced neuropathy is very low. A few cases of neuropathy due to darunavir have been reported, but it remains unclear if the PI is really the cause of neuropathy in these cases (Lorber 2013). Table 3: Neurotoxic drugs frequently used in HIV medicine NRTI ddI, d4T (ddC, no longer manufactured) Antibiotic dapsone, metronidazole, isoniazid Cytotoxic vincristine, etoposide Acute neuromuscular weakness syndrome In the course of an NRTI-induced lactic acidosis a life threatening tetraparesis resem- bling AIDP may occur. In most cases axonal peripheral nerve damage is found, but in a few patients demyelination is also detected. In addition, muscle biopsy reveals myositis or mitochondrial myopathy in some cases (Simpson 2004). Polyneuropathy and polyradiculopathy due to other diseases In patients with advanced HIV disease, mononeuritis multiplex may be caused by CMV infection or lymphoma. Acute or subacute polyradiculopathies of the cauda equina with rapidly progressive flaccid paraparesis of the legs, bowel dysfunction and sensory disturbances occur in the course of opportunistic infections (CMV, M. Other important causes of polyneuropathy are alcohol abuse, diabetes mellitus, malnutrition in patients with long-lasting gastrointestinal diseases, neoplastic diseases or cachexia. Diagnosis A diagnosis of neuropathy can usually be made based on medical history and clin- ical examination. Electrodiagnostic studies may be performed for confirmation and for differentiation from other diseases such as myelopathy. Cerebrospinal fluid analy- sis may be necessary if there is a suspicion of infection with, for example, CMV or syphilis. Sural nerve and muscle biopsy may be necessary only in atypical cases – for instance, painful DSSP with a high CD4 cell count and low viral load and without neurotoxic medication or other risk factors. Table 4 gives some recommendations for clinical practice. Occasionally, patients report complaints of burning feet, aches, pain and tingling but clinical examination and nerve conduction studies are unremarkable. In these cases symptoms might be due to an isolated small fiber neuropathy exclusively affect- ing the small unmyelinated vegetative nerve fibers. Diagnosis requires a punch skin biopsy with histological assessment of intraepidermal nerve fiber density or pain- related evoked potential conduction testing (Obermann 2007). Intravenous immunoglobulins and plasmapheresis have proven effective in the therapy of AIDP. In clini- cal trials on the treatment of CIDP, no difference in the efficacy of immunoglobu- lins, plasmapheresis or corticosteroids has been shown. However, an individual patient may only respond to one of the three options. In patients who only respond to higher dosages of corticosteroids, other immunosuppressive agents such as aza- thioprine, low dose weekly methotrexate or cyclosporine may replace long-term steroid therapy. We have seen CIDP patients who were in partial remission after tem- porary steroid therapy and who have remained stable for years with ART alone. In medication-related neuropathy the offending agent needs to be withdrawn. The intake of 2 g L-acetylcarnitine significantly reduced pain in HIV patients with neurotoxic neuropathy (Youle 2007). ART might improve the function of sensory nerves in a few cases, and therefore starting ART or optimizing a current ART should be considered in newly diagnosed DSSP. In most cases the neuropathic symp- toms still persist. Symptomatic treatment is directed at irritative symptoms such as pain and paresthesia. It is not effective against deficits of nerve function including sensory loss or weakness. The agents listed in Table 6 are recommended because they have proven useful in daily practice and because they interfere only slightly and in a predictable way with ART. A controlled study showed that lamotrigine was effective in reducing the symp- toms of neurotoxic neuropathy (Simpson 2003). The drug is well tolerated if one adheres to the slow dose escalation regimen and stops treatment or reduces the dose when a skin reaction occurs. In a small study, gabapentin was shown to be effective in reducing DSSP-induced pain (Hahn 2004). The advantages of this agent are good tolerability and lack of interference with ART. Pregabalin, an anticonvulsant drug similar to gabapentin, effectively relieves pain in studies of patients with painful dia- betic peripheral neuropathy (Rosenstock 2004). Like gabapentin, it does not inter- fere with ART and is well tolerated. It is commonly used in DSSP, although a recent trial in HIV patients did not show efficacy (Simpson 2010). The tricyclic antidepressants amitriptyline and nortriptyline both have significant anticholinergic side effects. The dose necessary for reducing neuropathic pain is in the same range as for treating depression and many patients can not tolerate these dosages. However, lower dosages have proved ineffective in DSSP. We use this agent with good success rates, although clinical trials for its use in HIV-associated neuropathy are lacking. The antidepressant dulox- etine, a serotonin-norepinephrine reuptake inhibitor, has been approved for the treat- ment of painful diabetic neuropathy. In our experience it is also useful in reducing pain in DSSP and toxic neuropathy in HIV+ patients. The anticonvulsant carba- mazepine is widely used for the treatment of neuropathic pain. However, it induces some enzymes of the CYP450 system and interferes significantly with ART.
Richmond Rascals. 12 Richmond Hill. Richmond-Upon-Thames. TW10 6QX tel: 020 8948 2250