As I’ve discussed previously, drug-gene testing, too drawn attention to as pharmacogenomics or pharmacogenetics, doesn’t really more work for psychiatric pharmaceuticals and disorders. Beings are buying a predict that’s not backed up by the research.
Recently, one company in this space produced a followup study to a large outpatient study of cases with clinical depression. Since the first study did not show any statistical significance in the study’s primary outcome bar, the company decided to simply re-crunch the data with other measures. Voila! Significance found.
In early 2019, Myriad Genetics, makers of the GeneSight Psychotropic test, had the results of a study they money published( Greden et al ., 2019 ). This is referred to as the GUIDED study — Genomics Used to Improve DEpression Decisions.
The primary appraise used in that study — the Hamilton Depression Rating Scale-1 7( HAM-D1 7) — demo no statistical significance between groupings of patients consuming medication guided by the drug-gene test to working group that had medication as usual. This magnitude is commonly used in depression drug tribulations as a” gold rule” for measuring the effectiveness of hollow treatment.
The difference in indication better scores between the two groups was 2.8%, with the” navigated charge”( the drug-gene testing) radical experiencing somewhat better manifestation betterment. This inconsistency, nonetheless, was not statistically significant.
The study too pointed out that the guided-care group experienced significantly improvements in response and remission rates.
I guess the lack of statistical significance on the HAM-D1 7 was bothersome to the company, as it subverts their commerce theme about the advantage of their drug-gene test. After all, the HAM-D1 7 was listed as the only primary aftermath measure in the Clinical Trials database. Since that outcome measure did not show statistical — much less clinical — implication, that indicated the GeneSight test perhaps wasn’t as supportive as the company claimed.
Twenty-five additional secondary measures were also registered. Of the ones actually reported in the study, these measures also expressed desegregated statistical significance for the guided-care group.
So the company decided to re-evaluate the data from the GUIDED study by looking at another measure — the HAM-D6. As you can likely guess, the HAM-D6 is a subset of the HAM-D1 7, consisting of merely 6 of the 17 questions be available on the longer measure. The HAM-D6 was developed to cut down on the time needed to administer the test. It too claims to more closely measure the evidences related to the DSM-IV diagnostic criteria for clinical depression — e.g ., it is more sensitive to detect depressive indications that are used in diagnosis.
This reanalysis could be done since they had all the data from the HAM-D1 7. All they had to do was just look at those 6 questions used on the shorter quantity to see what they might find. Here’s what the induce investigate of the brand-new study declarations in the company’s press release 😛 TAGEND
“The HAM-D6 scale has been shown to be a better measure of core depressive indications than the HAM-D1 7 magnitude, ” said Boadie W. Dunlop, M.D ., one of the study investigators and associate professor of Psychiatry and Behavioral Science at Emory University School of Medicine.
“This post hoc analysis furnishes further proof that the GeneSight test led to significant and clinically meaningful improvements in clinical upshots for cases with major depressive disorder relative to treatment-as-usual care.”
Now, frankly, this is just BS. If the original study had experienced statistical significance with the HAM-D1 7, there’s no way the same set of researchers would then go on to conduct what amounts to a big ol’ witch hunt, in my view. In fact, it begs the obvious question — if the HAM-D6 is such a superior measure, why wasn’t it squandered( even as a secondary measure) in the original study?
The brand-new study found that cases in the guided-care group experienced a 4.4% greater inconsistency in evidence better vs treatment-as-usual group. Voila again!
Since that difference is statistically significant, it is currently allows the researchers to claim that the GeneSight test is superior to treatment as usual according to a widely-accepted dimple appraise. The researchers delicately milked that 1.6% discrepancies between the two studies — the amount apparently needed to claim statistical significance.
Do It Matter to Patients Clinically?
Researchers can gurgle all day long about data and statistical significance. It represents little to most people. And it’s no wonder, because statistical significance in the data doesn’t automatically translate into clinical relevance in a doctor’s office.
In short-lived, do patients subjectively is of the opinion that 4.4% divergence in indication improvement in their lives?
Arguably, the answer in this case is a firm “maybe.” The response and remission rates found in the study speak more strongly to the possible impact that the guided-care arm had in care, since those in that group seemed to have a quicker response to the treatment they were prescribed, and were able to keep the depression manifestations at bay more often than those working in standard care.
But in terms of the actual subjective feeling of indication progress, I conclude the findings are emphatically less clear. I don’t believe that most cases would know much of a subjective divergence in their evidences in the guided-care group versus the treatment-as-usual group.
Keep in thought that both groups studied had less recession manifestations over epoch. It’s just that in the GeneSight group, those cases reported a slightly greater improvement in their symptoms.
If Myriad Genetics was looking for a grand-slam in terms of evidence clearly displaying the efficacy of their drug-gene test, I don’t think they found it in either of these studies. What the studies support instead, in my opinion, is a slightly better outcome for some patients who make the GeneSight test. It is not an outcome that I believe to be clinically important , nor justifies the widespread consume of any GeneSight test for psychiatric agitations at this time.
Bech, P.( 2006 ). Rating magnitudes in depression: limits and dangers. Dialogies in Clinical Neuroscience, 8( 2 ), 207 -2 15.
Dunlop BW, Parikh SV, Rothschild AJ, Thase ME, DeBattista C, Conway CR, Forester BP, Mondimore FM, Shelton RC, Macaluso M, Logan J, Traxler P, Li J, Johnson H, Greden JF.( 2019 ). Comparing sensitivity to change using the 6-item versus the 17 -item Hamilton depression rating scale in the GUIDED randomized limited visitation. BMC Psychiatry, 19( 1 ): 420. doi: 10.1186/ s12888-019-2410-2.
Greden JF, Parikh SV, Rothschild AJ, Thase ME, Dunlop BW, DeBattista C, Conway CR, Forester BP, Mondimore FM, Shelton RC, Macaluso M, Li J, Brown K, Gilbert A, Burns L, Jablonski MR, Dechairo B.( 2019 ). Impact of pharmacogenomics on clinical outcomes in major depressive disorder in the GUIDED trial: A massive, patient- and rater-blinded, randomized, controlled study. J Psychiatr Res ., 111:59 -6 7. doi: 10.1016/ j.jpsychires. 2019.01.003. Epub 2019 Jan 4.
Thase ME, Parikh SV, Rothschild AJ, Dunlop BW, DeBattista C, Conway CR, Forester BP, Mondimore FM, Shelton RC, Macaluso M, Li J, Brown K, Jablonski MR, Greden JF.( 2019 ). Impact of Pharmacogenomics on Clinical Outcomes for Patients Taking Medications With Gene-Drug Interactions in a Randomized Controlled Trial. J Clin Psychiatry, 80( 6 ). pii: 19 m12910. doi: 10.4088/ JCP. 19 m12910.
Read more: psychcentral.com