Anavex Life Sciences Corp (AVXL)

[sokol]

Effectiveness of Drugs - It’s Complicated But..

I have provided references below that show that many drugs are approved even though the drugs benefit a small percentage of people that take them. "The top ten highest-grossing drugs in the United States help between 1 in 25 and 1 in 4 of the people who take them .... For some drugs, such as statins — routinely used to lower cholesterol — as few as 1 in 50 may benefit1. " See references below.

If Anavex can approve safety and efficacy for a certain class of patients based on — genetic and environmental factors, among others — that shows a response to treatment.... it may obtain approval of AVXL 2-73.

1. How effective are common medications: a perspective based on meta-analyses of major drugs

''We found that some of the medications have relatively low effect sizes with only 11 out of 17 of them showing a minimal clinically important difference. Efficacy was often established based on surrogate outcomes and not the more relevant patient-oriented outcomes. As the interpretation of the efficacy of medication is complex, more training for physicians might be needed to get a more realistic view of drug efficacy. ''

https://bmcmedicine.biomedcentral.com/articles/10.1186/s12916-015-0494-1


2. ''The effectiveness of a drug is closely linked to its safety. It is for this reason that the legal approval for the administration of a particular drug is assessed on a risk/benefit analysis. If a drug is known to generate significant side effects in a consumer, it will have a reduced effectiveness, notwithstanding the drug's ability to counter a particular physical condition.''

https://www.encyclopedia.com/sports/sports-fitness-recreation-and-leisure-magazines/drug-effectiveness

3. Personalized medicine: Time for one-person trials

''Precision medicine requires a different type of clinical trial that focuses on individual, not average, responses to therapy, says Nicholas J. Schork....

...Every day, millions of people are taking medications that will not help them. The top ten highest-grossing drugs in the United States help between 1 in 25 and 1 in 4 of the people who take them (see 'Imprecision medicine'). For some drugs, such as statins — routinely used to lower cholesterol — as few as 1 in 50 may benefit1. There are even drugs that are harmful to certain ethnic groups because of the bias towards white Western participants in classical clinical trials2....

....Classical clinical trials harvest a handful of measurements from thousands of people. Precision medicine requires different ways of testing interventions. Researchers need to probe the myriad factors — genetic and environmental, among others — that shape a person's response to a particular treatment....

...Discovering that an intervention works well in certain groups happens relatively rarely and often by chance. Researchers typically get disappointing results with a drug in large, population-based trials. This leads them to conduct ad hoc post-trial analyses, to try to identify the factors that cause some of the people in the trial to seem to be responsive3.

For instance, the drug Gleevec (imatinib) was found to double survival rates of leukaemia patients4 with a chromosomal abnormality in their tumours called the Philadelphia translocation. Similarly, it turns out that Erbitux (cetuximab) improves the survival of people with colorectal cancer whose tumour cells carry a mutated EGFR gene but not a mutated KRAS gene5.

This approach to discovery is inefficient at best. Conventional phase III trials involve thousands of people. The intervention being tested is often given at random to one group while another group receives a sham treatment, such as a sugar pill or the standard treatment that physicians would give such patients. Because scant data are collected on factors such as genetics, lifestyles and diets, the results of these trials often indicate the need for yet another study to validate the effectiveness of the intervention among the apparent responders and to establish the underlying mechanisms....

https://www.nature.com/news/personalized-medicine-time-for-one-person-trials-1.17411