Posted By : Margaret Garland
Category : lainnya
So which is it? Ineffective or unprecedented?
TauRx Alzheimer's Drug LMTX Fails inwards Large Study Although Some Benefit Seen
Wednesday, 27 Jul 2016 | 11:23 AM ET
TauRx Pharmaceuticals' experimental Alzheimer's drug LMTX failed to improve cognitive in addition to functional skills inwards patients amongst mild to moderate Alzheimer's disease, a large, late-stage study showed.
But inwards a perplexing twist, the drug did demonstrate a important produce goodness inwards well-nigh xv pct of patients inwards the lawsuit who were non taking other measure Alzheimer's drugs, according to the findings released on Midweek at the Alzheimer's Association International Conference inwards Toronto.
LMTX was ineffective inwards a clinical lawsuit of 891 patients amongst Alzheimer's affliction (AD), although a post hoc analysis inwards a pocket-sized subgroup of patients showed a produce goodness for those taking no other medications for AD (when compared to an inappropriate command group).
lol this RCT really had a negative result. Fascinating to compare UK vs USA media coverage. https://t.co/z4hfC3DSB8 https://t.co/Jgk8wsleci— ben goldacre (@bengoldacre) July 27, 2016
Ben Goldacre, Chris Chambers, in addition to others on Twitter took the UK media to chore for their misleading articles on the outcome of the lawsuit conducted past times TauRx Pharmaceuticals.
As the shout out implies, TauRx is developing Alzheimer's treatments based on disrupting tau protein, which accumulates inwards pathological tangles inwards the brain. Tau aggregation inhibitors are presumed to disrupt these tangles, thereby slowing neurodegeneration in addition to retention loss. The degradation of tau aggregates in vitro was outset demonstrated twenty years agone (Wischik et al., 1996), using the stain methylene blue. LMTX is a variant of methylene blue, which turns urine blue. For that reason, the placebo grouping inwards the TauRx lawsuit received a tiny amount of the drug for blinding purposes.
The clinical lawsuit protocol is NCT01689246, Safety in addition to Efficacy Study Evaluating TRx0237 inwards Subjects With Mild to Moderate Alzheimer's Disease. The original enrollment across 121 sites was estimated at 833, in addition to the original duration was 12 months. The duration was changed to 15 months well-nigh a yr later, in addition to v other outcome measures were added. And a secondary outcome mensurate (ADCS-ADL23) in addition to a primary outcome mensurate (ADCS-CGIC) were swapped.
The fellowship press liberate used a vague headline (TauRx Reports First Phase 3 Results for LMTX®) to denote the results, simply led off amongst the subgroup analysis (no surprise):
TauRx Therapeutics Ltd today announced Phase 3 clinical lawsuit results that demonstrate handling amongst LMTX®, the company's novel tau aggregation inhibitor, had a marked beneficial outcome on commutation measures of Alzheimer's disease inwards patients amongst mild or moderate forms of the disease.
While the TRx-237-015 study inwards 891 subjects failed to run across its co-primary endpoints, clinically meaningful in addition to statistically important reductions inwards the charge per unit of measurement of affliction progression were observed across iii commutation measures inwards patients who were treated amongst LMTX® every bit their solely Alzheimer's affliction medication. These iii commutation measures comprised a cognitive assessment (ADAS-Cog), a functional assessment (ADCS-ADL) in addition to an assessment of the grade of encephalon atrophy (lateral ventricular volume, LVV, every bit measured past times MRI). An abstract of the results volition last presented during an opened upward session at the 2016 Alzheimer's Association International Conference (AAIC) inwards Toronto, Canada this afternoon past times Dr. Serge Gauthier, CM, MD.
The ADCS-ADL was originally a secondary outcome measure, in addition to hippocampal book (not reported) was included every bit an “Other” outcome mensurate along amongst the lateral ventricle book measurements. Keep inwards hear these results are preliminary (not peer-reviewed). However, given the possibility of a truthful positive handling effect, I tin make the sack sympathize why publication would last of secondary importance. There should last no delay inwards starting AD patients on an effective novel in addition to proven handling (which this is not).
It took a spell to divulge the conference abstract past times Gaultier et al. (2016), simply an excerpt is below. The actual results were non included — the abstract aimed to “highlight the potential therapeutic value” of LMTX (also called LMTM in addition to TRx-0237) — simply the text did cite the “85% were taking approved AD treatments” expression of the study.
TRx-0237) is a novel stabilized reduced shape of the methylthioninium moiety amongst potential for efficacy inwards handling of Alzheimer's disease. ... It acts every bit a selective tau aggregation inhibitor inwards vitro in addition to inwards transgenic mouse models The acquaint 15-month double-blind, placebo-controlled lawsuit (NCT01689246) was performed inwards patients amongst likely AD, MMSE score inwards the make 14-26, Clinical Dementia Rating 1-2 in addition to historic menses < xc years. Patients were randomized 3:3:4 to have oral LMTM at doses of 150 or 250 mg/day or placebo (containing 8 mg/day, to hold blinding) respectively. Primary efficacy outcomes were alter from baseline on cognitive (ADAS-Cog) in addition to functional (ADCS-ADL) scores. Three-monthly assessment included magnetic resonance imaging (MRI) every bit a affliction modifying outcome. Other secondary outcomes included ADCS-CGIC in addition to MMSE. Results: Influenza A virus subtype H5N1 full of 891 patients were randomized, of whom 62% were female. Approved AD treatments were existence taken inwards 85%. The hateful historic menses was 70.6 (SD 9.0) years in addition to baseline MMSE score was 18.7 (SD 3.4). ... The study efficacy in addition to security outcomes volition last reported. The outcomes of this stage 3 lawsuit volition highlight the potential therapeutic value of tau aggregation inhibitor therapy inwards AD. Influenza A virus subtype H5N1 instant stage 3 lawsuit of LMTM for AD volition last completed in addition to reported after inwards 2016.
[The entire abstract amongst authors in addition to affiliations is at the terminate of this post.]
The 15% who benefited from LMTX® were the patients who were non taking whatsoever other medications for dementia (e.g., acetylcholinesterase inhibitors). This monotherapy subgroup was compared to the entire placebo group, not to the subgroup of placebo patients non on whatsoever other dementia meds (as pointed out past times @bengoldacre). It was dainty to read critical coverage of the TauRx spin (and media reporting) at Forbes, BuzzFeed, in addition to Quartz.
Meanwhile, New Scientist updated their headline (and url) to to a greater extent than accurately reverberate reality.
Is it worthwhile for TauRx to pursue a proper clinical lawsuit of LMTX every bit a monotherapy? Maybe. The large mystery is why LMTX didn't piece of job inwards patients taking the commons medications for dementia. There's no convincing machinery to explicate that strange final result (Wischik: “other Alzheimer’s treatments tending to clear toxic cloth out of the brain, in addition to may also clear away LMTX too”). Or it could last a p-hacked faux positive, or a business office of milder severity or diagnostic issues or study site inwards the 15%. If TauRx is genuinely confident that LMTX taken lone tin make the sack irksome the progression of AD past times 80%, thus run around other randomized controlled study where LMTX + no AD meds is compared to placebo + no AD meds.
Meanwhile, exaggerated reporting on “the outset drug to stop Alzheimer’s” is highly unethical.
ADDENDUM (Aug two 2016): Influenza A virus subtype H5N1 damning article at Alzforum says, In First Phase 3 Trial, the Tau Drug LMTM Did Not Work. Period.
On the master copy primary results slide, affliction progression curves for both doses of drug in addition to the placebo were practically identical. Scientists’ disappointment at this finding shortly turned into disbelief when Gauthier went on to acquaint a subgroup analysis that held no statistical acceptance yet purported to demonstrate a strong produce goodness on knowledge in addition to encephalon atrophy.
Thanks to @MaikWallas for the link.
AAIC Conference Abstract
Phase 3 Trial of the Tau Aggregation Inhibitor Leuco-Methylthioninium-Bis(hydromethanesulfonate) (LMTM) inwards Mild to Moderate Alzheimer's Disease
Serge Gauthier, MD1; Howard H Feldman, MD2; Lon southward Schneider, MD, MS3; Gordon Wilcock, MD4; Giovanni B Frisoni, MD5; Jiri Hardlund, MD6; Karin Kook, PhD7; Damon J Wischik, PhD6; Bjoern O Schelter, PhD8; John chiliad Storey, PhD6,8; Charles R Harrington, PhD6,8 in addition to Claude chiliad Wischik, MD, PhD6,8, (1)McGill University Research Centre for Studies inwards Aging, Verdun, QC, Canada, (2)University of British Columbia, Vancouver, BC, Canada, (3)Keck School of Medicine of USC, Los Angeles, CA, USA, (4)Oxford University, Oxford, United Kingdom, (5)Universite de Geneve, Geneve, Switzerland, (6)TauRx Therapeutics Ltd, Aberdeen, United Kingdom, (7)Salamandra LLC, Bethesda, MD, USA, (8)University of Aberdeen, Aberdeen, United Kingdom
Background: Leuco-methylthioninium-bis(hydromethanesulfonate) (LMTM; TRx-0237) is a novel stabilized reduced shape of the methylthioninium (MT) moiety (Harrington et al. J Biol Chem 2015;290:10862) amongst potential for efficacy inwards handling of Alzheimer's affliction (AD). Influenza A virus subtype H5N1 previous lawsuit using the oxidized shape of MT identified dose dependent absorption limitations (Wischik et al. J Alzheimers Dis 2015;44:705). LMTM is amend absorbed in addition to tolerated (Baddeley et al. J Pharmacol Exptl Therapeutics 2015;352:110) permitting higher doses to last tested. It acts every bit a selective tau aggregation inhibitor inwards vitro (Harrington et al. J Biol Chem 2015;290:10862) in addition to inwards transgenic mouse models (Melis et al. Behav Pharmacol 2015;26:353). Methods: The acquaint 15-month double-blind, placebo-controlled lawsuit (NCT01689246) was performed inwards patients amongst likely AD, Mini-Mental State Examination (MMSE) score inwards the make 14-26, Clinical Dementia Rating (CDR) 1-2 in addition to historic menses < xc years. Patients were randomized 3:3:4 to have oral LMTM at doses of 150 or 250 mg/day or placebo (containing 8 mg/day, to hold blinding) respectively. Primary efficacy outcomes were alter from baseline on cognitive (Alzheimer's Disease Assessment Scale cognitive subscale; ADAS-Cog) in addition to functional (Alzheimer's Disease Cooperative Study Activities of Daily Living; ADCS-ADL) scores. Three-monthly assessment included magnetic resonance imaging (MRI) every bit a affliction modifying outcome. Other secondary outcomes included ADCS-CGIC in addition to MMSE. Results: Influenza A virus subtype H5N1 full of 891 patients were randomized, of whom 62% were female. Approved AD treatments were existence taken inwards 85%. The hateful historic menses was 70.6 (SD 9.0) years in addition to baseline MMSE score was 18.7 (SD 3.4). Dementia was of moderate severity (MMSE score 14-19) inwards 61%. The study efficacy in addition to security outcomes volition last reported. Conclusions: The outcomes of this stage 3 lawsuit volition highlight the potential therapeutic value of tau aggregation inhibitor therapy inwards AD. Influenza A virus subtype H5N1 instant stage 3 lawsuit of LMTM for AD volition last completed in addition to reported after inwards 2016.