Showing posts sorted by relevance for query RNA. Sort by date Show all posts
Showing posts sorted by relevance for query RNA. Sort by date Show all posts

Saturday, May 24, 2014

Compound reverses symptoms of Alzheimer's disease in mice

"It reversed learning and memory deficits and brain inflammation in mice that are genetically engineered to model Alzheimer's disease," Farr said. "Our current findings suggest that the compound, which is called antisense oligonucleotide (OL-1), is a potential treatment for Alzheimer's disease."

Farr cautioned that the experiment was conducted in a mouse model. Like any drug, before an antisense compound could be tested in human clinical trials, toxicity tests need to be completed.

Antisense is a strand of molecules that bind to messenger RNA, launching a cascade of cellular events that turns off a certain gene.

In this case, OL-1 blocks the translation of RNA, which triggers a process that keeps excess amyloid beta protein from being produced. The specific antisense significantly decreased the over expression of a substance called amyloid beta protein precursor, which normalized the amount of amyloid beta protein in the body. Excess amyloid beta protein is believed to be partially responsible for the formation of plaque in
the brain of patients who have Alzheimer's disease.

Scientists tested OL-1 in a type of mouse that overexpresses a mutant form of the human amyloid beta precursor gene. Previously they had tested the substance in a mouse model that has a natural mutation causing it to overproduce mouse amyloid beta. Like people who have Alzheimer's disease, both types of mice have age-related impairments in learning and memory, elevated levels of amyloid beta protein that stay in the brain and increased inflammation and oxidative damage to the hippocampus  the part of the brain responsible for learning and memory.

"To be effective in humans, OL-1 would need to be effective at suppressing production of human amyloid beta protein," Farr said.

Scientists compared the mice that were genetically engineered to overproduce human amyloid beta protein with a wild strain, which served as the control. All of the wild strain received random antisense, while about half of the genetically engineered mice received random antisense and half received OL-1. 

The mice were given a series of tests designed to measure memory, learning and appropriate behavior, such as going through a maze, exploring an unfamiliar location and recognizing an object. 

Scientists found that learning and memory improved in the genetically engineered mice that received OL-1 compared to the genetically engineered mice that received random antisense. Learning and memory were the same among genetically engineered mice that received OL-1 and wild mice that received random antisense.

They also tested the effect of administering the drug through the central nervous system, so it crossed the blood brain barrier to enter the brain directly, and of giving it through a vein in the tail, so it circulated through the bloodstream in the body. They found where the drug was injected had little effect on learning and memory.

Ref http://iospress.metapress.com/content/px72758w0158103u/?issue=4&genre=article&spage=1005&issn=1387-2877&volume=40




































Monday, October 19, 2009

Using RNAi-based Technique, Scientists Find New Tumor Suppressor Genes In Lymphoma...

In one of my earlier blog about RNAi, I did mention about the award of USPTO notices to RXi Pharmaceuticals Corporation. But these results are really interesting, the CSHL team’s discovery stems from their use of a powerful technology called RNA interference (RNAi), which suppresses gene activity. The scientists employed RNAi to screen hundreds of candidate tumor-suppressors in living mice, using small hairpin-shaped RNA (shRNA) molecules that attach to specific genes with exquisite specificity and switch them off. In the newly reported experiments, this process revealed more than 10 genes whose deactivation accelerates the development of deadly lymphomas tumors of the immune system in the mice.

The CSHL team’s high-throughput screening strategy to functionally identify cancer genes has thus not only provided insights into cancer development but has also pointed the way toward therapeutic refinements. The team is planning a broader RNAi-based screen that will expand into other tumor models. For details...

Sunday, October 4, 2009

RXi receives USPTO notices of allowance for certain siRNA sequence-specific patent applications..

In my earlier blog (January 25, 2009), titled "Diverse use of Nucleic acids....." I did mention about the RNA interference (RNAi) technology. Yes the dream has come true now "RXi Pharmaceuticals Corporation" has received Notices of Allowance from USPTO for small interfering RNA (siRNA) sequences targeting superoxide dismutase (SOD1), Amyloid beta (A4) precursor protein (APP), interleukin-1 receptor-associated kinase 4 (IRAK4), hepatocyte growth factor receptor (MET protooncogene) and cyclin-dependent kinase (cdk) inhibitor p27 (also known as MET protooncogene). Hope these class of compounds will get a boost and some new drugs from these class of compounds in the near future.....

More :
RXi receives USPTO notices of allowance for certain siRNA sequence-specific patent applications

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Saturday, December 5, 2009

First live targeting of tumors with RNA-based technology

Researchers at Duke University Medical Center have devised a way they might deliver the right therapy directly to tumors using special molecules, called aptamers, (Aptamers are oligonucleotides or peptide molecules that bind to a specific target molecule) which specifically bind to living tumor tissue.......

More....First live targeting of tumors with RNA-based technology

Monday, March 1, 2021

FDA Approves Amondys 45 (casimersen) Injection for the Treatment of Duchenne Muscular Dystrophy (DMD) in Patients Amenable to Skipping Exon 45

In continuation of my update on antisense oligonucleotides 

Sarepta Therapeutics, Inc. the leader in precision genetic medicine for rare diseases, today announced that the U.S. Food and Drug Administration (FDA) has approved Amondys 45 (casimersen). Amondys 45 is an antisense oligonucleotide from Sarepta’s phosphorodiamidate morpholino oligomer (PMO) platform, indicated for the treatment of Duchenne muscular dystrophy (DMD) in patients with a confirmed mutation amenable to exon 45 skipping. This indication is based on a statistically significant increase in dystrophin production in skeletal muscle observed in patients treated with Amondys 45, which is reasonably likely to predict clinical benefit for those patients who are exon 45 amenable. Consistent with the accelerated approval pathway, the continued approval of Amondys 45 may be contingent on confirmation of a clinical benefit in confirmatory trials.

The ESSENCE trial – a placebo-controlled confirmatory trial to support the Amondys 45 approval – is ongoing and expected to conclude in 2024.

Although kidney toxicity was not observed in the clinical studies with Amondys 45, kidney toxicity, including potentially fatal glomerulonephritis, has been observed after administration of some antisense oligonucleotides. Kidney function should be monitored in patients taking Amondys 45. In the clinical trial, the most common adverse reactions observed in at least 20% of patients treated with Amondys 45 and at least 5% more frequently than in placebo were (Amondys 45, placebo): upper respiratory tract infections (65%, 55%), cough (33%, 26%), fever (33%, 23%), headache (32%, 19%), joint pain (21%, 10%), and pain in mouth and throat (21%, 7%).

“This is an important day for Sarepta and, far more importantly, for the patients that we serve. After years of scientific commitment, investment and development, the approval of Amondys 45, Sarepta’s third approved RNA therapy, offers treatment to the 8% of the DMD community who have a confirmed exon 45 amenable mutation,” said Doug Ingram, president and chief executive officer, Sarepta. “Along with our other approved RNA therapies, we can now offer treatment options for nearly 30% of Duchenne patients in the U.S. And our commitment to bring therapies to the greatest percentage of the DMD community as soon as possible continues.”

“Decades of research and commitment have fueled and now accelerate our progress towards new treatments for Duchenne,” said Marissa Penrod, founder of Team Joseph and parent of an 18-year old with Duchenne. “The extraordinary diligence and persistence of the Duchenne community – patients and families, clinicians and researchers – have led us to today’s approval, where we now have exon-skipping treatments for almost a third of those with Duchenne.”   


Monday, February 23, 2015

Isis Pharmaceuticals begins ISIS-DMPK Rx clinical study in DM1 patients

Isis Pharmaceuticals, Inc. (NASDAQ: ISIS) announced  that it has initiated a study for ISIS-DMPKRx in patients with Myotonic Dystrophy Type 1 (DM1). DM1 is a rare genetic neuromuscular disease caused by the production of toxic dystrophia myotonica-protein kinase (DMPK) RNA in cells. ISIS-DMPKRx is specifically designed to reduce toxic DMPK RNA.

"The Myotonic Dystrophy Foundation is pleased that Isis is advancing to the next phase of clinical trials for ISIS-DMPKRx," said Molly White, executive director of the Myotonic Dystrophy Foundation. "Myotonic Dystrophy, the most common form of muscular dystrophy, is a devastating disease with no therapeutic option. Myotonic dystrophy research has accelerated significantly in the last 10 years, helping bring about the innovative science behind ISIS-DMPKRx, a drug that specifically targets the genetic defect that causes myotonic dystrophy type 1. We applaud Isis for investing in and leading drug development efforts for myotonic dystrophy type 1, and we appreciate the commitment Isis Pharmaceuticals has made to improve the lives of patients in our community."

"We have an innovative and productive partnership with Biogen Idec in developing drugs to treat severe and rare diseases, like DM1. In just under two and a half years, we have been able to discover and complete early development on ISIS-DMPKRx, which includes completing a Phase 1 single ascending-dose study in healthy volunteers. Today we advance this program into patients," said B. Lynne Parshall, chief operating officer at Isis. "The speed at which we have advanced ISIS-DMPKRx highlights the productive and collaborative nature of our partnership."

Sunday, November 15, 2009

A tetracycline derivative for the treatment of Spinal Muscular Atrophy .....

A chemical cousin of the common antibiotic tetracycline (PTK-SMA1) might be useful in treating spinal muscular atrophy (SMA), a currently incurable disease that is the leading genetic cause of death in infants. This is the finding of a research collaboration involving Adrian Krainer, Ph.D., of Cold Spring Harbor Laboratory (CSHL) and scientists from Paratek Pharmaceuticals and Rosalind Franklin University of Medicine and Science.

About SMA :

SMA is caused by mutations in a gene called Survival of Motor Neuron 1 (SMN1), resulting in a decrease in the levels of SMN protein in the motor neurons of the spinal cord -- the cells that control muscle activity. Without the protein, these neurons degenerate, and infants born with the mutations progressively lose the ability to move, swallow, and breathe. There are no approved therapies for the treatment of SMA.

Mode of action of PTK-SMA1 :

The new molecule boosts the levels of SMN protein in cells by fixing a mistake in a cellular processing mechanism called RNA splicing. The drug candidate targets the splicing of a gene called SMN2, which is essentially a back-up copy to the SMN1 gene that’s mutated beyond repair in SMA patients. SMN2 doesn’t compensate for the loss of SMN1, however, because it produces too little functional protein. Most of the protein that is produced is missing a single important piece, without which the protein rapidly degrades. The significance of this finding is in the fact that “PTK-SMA1 is the only small molecule known to specifically alter RNA splicing by directly and solely targeting the splicing reaction” . Other molecules that affect splicing also affect other cellular processes, thus diluting their potency, and potentially increasing the risk of side effects. PTK-SMA1 has the added advantage of being a derivative of tetracyclines, which are nontoxic and have demonstrated safety in humans...

Source : http://stm.sciencemag.org/content/1/5/5ra12.abstract.





Saturday, May 18, 2019

FDA Approves Dovato (dolutegravir/lamivudine) for HIV-1 Infection

In continuation of my update on Dolutegravir & Lamivudine



Dolutegravir.svg
Dolutegravir (DTG)

Lamivudine structure.svg
Lamivudine, commonly called 3TC

ViiV Healthcare  announced the US Food and Drug Administration (FDA) approval of Dovato, a complete, once-daily, single-tablet regimen of dolutegravir (DTG) 50 mg and lamivudine (3TC) 300 mg for the treatment of HIV-1 infection in adults with no antiretroviral (ARV) treatment history and with no known resistance to either DTG or 3TC. Dovato, a two-drug regimen (2DR), reduces exposure to the number of ARVs from the start of treatment, while still maintaining the efficacy and high barrier to resistance of a traditional DTG-based three-drug regimen.
Deborah Waterhouse, CEO, ViiV Healthcare, said: “Building on our innovative portfolio of medicines, Dovato is powered by dolutegravir, an antiretroviral included in multiple combination therapies and the most prescribed integrase inhibitor in the world, 2 coupled with the established profile of lamivudine. With Dovato, the first complete, single-tablet, two-drug regimen for treatment-naïve adults, ViiV Healthcare is delivering what patients are requesting—a chance to treat their HIV-1 infection with as few drugs as possible, marking a significant step in HIV treatment.”
The approval of Dovato is supported by the landmark global GEMINI 1 and 2 studies that included more than 1,400 HIV-1 infected adults. In these studies, DTG + 3TC demonstrated non-inferiority based on plasma HIV-1 RNA <50 copies per milliliter (c/mL), a standard measure of HIV-1 control, at Week 48 when compared to a three-drug regimen of DTG and two nucleoside reverse transcriptase inhibitors (NRTIs), tenofovir disoproxil fumarate/emtricitabine (TDF/FTC), in treatment-naïve, HIV-1 infected adults. The safety results for DTG + 3TC seen in GEMINI 1 and 2 were consistent with the product labelling for DTG and 3TC. No patient who experienced virologic failure in either treatment arm developed treatment-emergent resistance.
Pedro Cahn, principal investigator for the GEMINI study program said: “People are now living longer with HIV and will spend a lifetime taking drugs to suppress their virus. The approval of the fixed dose combination of dolutegravir and lamivudine, a complete, single-tablet, two-drug regimen, marks a pivotal moment in the treatment of HIV-1. Treatment-naïve people living with the virus have a powerful option that delivers non-inferior efficacy to a dolutegravir-based three-drug regimen, allowing them to take fewer ARVs and get and remain suppressed.”
Jeff Berry, Test Positive Aware Network (TPAN), said: “The approval of Dovato is a welcome paradigm shift, as it brings an innovative treatment approach to newly diagnosed adults with HIV-1. By exposing patients to fewer drugs at the start of treatment, the hope is to help address concerns arising from overall management of prolonged ARV therapy.”
DTG/3TC as a complete, once-daily, single-tablet, two-drug regimen for HIV-1 therapy is currently under review by the European Medicines Agency (EMA) and regulatory authorities in Canada, Australia, Switzerland, and South Africa and several additional submissions are planned throughout 2019.

About Dovato (dolutegravir/lamivudine)

Dovato is approved as a complete regimen for the treatment of HIV-1 infection in adults with no known antiretroviral treatment history and with no known substitutions associated with resistance to either dolutegravir or lamivudine. Dovato is a once-daily, single-tablet, two-drug regimen that combines the integrase strand transfer inhibitor (INSTI) dolutegravir (Tivicay, 50 mg) with the nucleoside analogue reverse transcriptase inhibitor (NRTI) lamivudine (Epivir, 300 mg).
Like a DTG-based three-drug regimen, Dovato uses only two drugs to inhibit the viral cycle at two different sites. INSTIs, like dolutegravir, inhibit HIV replication by preventing the viral DNA from integrating into the genetic material of human immune cells (T-cells). This step is essential in the HIV replication cycle and is also responsible for establishing chronic infection. Lamivudine is an NRTI that works by interfering with the conversion of viral RNA into DNA which in turn stops the virus from multiplying.

https://en.wikipedia.org/wiki/Dolutegravir
https://en.wikipedia.org/wiki/Lamivudine

Friday, May 24, 2013

Scientists Uncover How Grapefruits Provide a Secret Weapon in Medical Drug Delivery...

Lipids (right panel first three tubes) derived from grapefruit. GNVs can efficiently deliver a variety of therapeutic agents, including DNA, RNA (DIR-GNVs), proteins and anti-cancer drugs (GNVs-Drugs) as demonstrated in this study. University of Louisville researchers have uncovered how to create nanoparticles using natural lipids derived from grapefruit, and have discovered how to use them as drug delivery vehicles.


"These nanoparticles, which we've named grapefruit-derived nanovectors (GNVs), are derived from an edible plant, and we believe they are less toxic for patients, result in less biohazardous waste for the environment, and are much cheaper to produce at large scale than nanoparticles made from synthetic materials," Zhang said.


The researchers demonstrated that GNVs can transport various therapeutic agents, including anti-cancer drugs, DNA/RNA and proteins such as antibodies. Treatment of animals with GNVs seemed to cause less adverse effects than treatment with drugs encapsulated in synthetic lipids.

"Our GNVs can be modified to target specific cells -- we can use them like missiles to carry a variety of therapeutic agents for the purpose of destroying diseased cells," he said. "Furthermore, we can do this at an affordable price."

The therapeutic potential of grapefruit derived nanoparticles was further validated through a Phase 1 clinical trial for treatment of colon cancer patients. So far, researchers have observed no toxicity in the patients who orally took the anti-inflammatory agent curcumin encapsulated in grapefruit nanoparticles.

Ref : http://www.nature.com/ncomms/journal/v4/n5/full/ncomms2886.html

Thursday, July 18, 2013

The ribosome: New target for antiprion medicines

New research results from Uppsala University, Sweden, show that the key to treating neurodegenerative prion diseases such as mad cow disease and Creutzfeldt-Jakob disease may lie in the ribosome, the protein synthesis machinery of the cell. The results were recently published in the Journal of Biological Chemistry.

"We have now shown that the protein folding activity of the ribosome (PFAR) is most likely involved in prion propagation and thus, can be a specific target for antiprion medicines. If we understand the mechanism fully, we will be able to find ways to stop that too.," says Suparna Sanyal, senior lecturer at the Department of Cell and Molecular Biology, Uppsala University .
The ribosome is the protein synthesis machinery of the cell. The mechanism of protein synthesis by the ribosome is well characterized, while PFAR is a rather recent discovery. PFAR is a ribosomal RNA dependent function of the large subunit of the ribosome irrespective of its source. The PFAR center closely overlaps the peptidyl transferase center although the nucleobases responsible for these two functions are not all common.

"Our results show that two prion inhibitors 6-aminophenanthridine (left struct) and guanabenz acetate (right struct) implement antiprion activity by binding to ribosomal RNA and inhibiting PFAR. Thus, the ribosome and more specifically PFAR is the new target for antiprion medicines. Furthermore, we have developed an in vitro PFAR assay, which can be used as a platform for screening prion inhibitors in a high-throughput fashion. This assay is much more time and cost-effective than standard prion assays," says Suparna Sanyal....
 The ribosome: New target for antiprion medicines

 

Monday, July 9, 2012

Achillion Announces Additional Proof-of-Concept Data With ACH-2684 for the Treatment of Hepatitis C

Achillion Announces Additional Proof-of-Concept Data With ACH-2684 for the Treatment of Hepatitis C: Achieves Up to 3.73 log10 Reduction in Genotype 1 HCV RNA After Three Days of Treatment With Once-Daily 400 mg ACH-2684 in Phase 1b Study : Achillion Pharmaceuticals, Inc. (Nasdaq:ACHN) today reported...

Achillion Pharmaceuticals, Inc. reported proof-of-concept data from a Phase 1b clinical trial demonstrating that patients with chronic hepatitis C (HCV) genotype 1 (GT 1) treated with ACH-2684 (see below structure), a second-generation protease inhibitor, achieved a mean maximum 3.73 log10 reduction in HCV RNA after three-day 400 mg monotherapy with once-daily (QD) dosing. The compound also demonstrated good safety and tolerability both in healthy volunteers and in patients with HCV.

 "We believe ACH-2684, with its potent antiviral activity achieved without boosting and once-daily dosing, is one of the most intriguing protease inhibitors in clinical development for the treatment of HCV,"...



Thursday, May 26, 2016

FDA Approves Odefsey (emtricitabine, rilpivirine and tenofovir alafenamide) for the Treatment of HIV-1 Infection

Gilead Sciences, Inc announced that the U.S. Food and Drug Administration (FDA) has approved Odefsey (emtricitabine 200 mg/rilpivirine 25 mg/tenofovir alafenamide 25 mg or R/F/TAF) for the treatment of HIV-1 infection in certain patients. Emtricitabine and tenofovir alafenamide are from Gilead Sciences and rilpivirine is from Janssen Sciences Ireland UC, one of the Janssen Pharmaceutical Companies of Johnson & Johnson (Janssen). Odefsey is Gilead’s second TAF-based regimen to receive FDA approval and represents the smallest pill of any single tablet regimen for the treatment of HIV.

Emtricitabine skeletal.svgEmtricitabine  Rilpivirine.svgRilpivirine  Tenofovir alafenamide structure.svgTenofovir alafenamide

Odefsey is indicated as a complete regimen for the treatment of HIV-1 infection in patients 12 years of age and older who have no antiretroviral treatment history and HIV-1 RNA levels less than or equal to 100,000 copies per mL. Odefsey is also indicated as replacement for a stable antiretroviral regimen in those who are virologically-suppressed (HIV-1 RNA less than 50 copies per mL) for at least six months with no history of treatment failure and no known substitutions associated with resistance to the individual components of Odefsey. No dosage adjustment of Odefsey is required in patients with estimated creatinine clearance greater than or equal to 30 mL per minute.
Odefsey has a boxed warning in its product label regarding the risks of lactic acidosis/severe hepatomegaly with steatosis, and post treatment acute exacerbation of hepatitis B.
TAF is a novel targeted prodrug of tenofovir that has demonstrated high antiviral efficacy similar to and at a dose less than one-tenth that of Gilead’s Viread (tenofovir disoproxil fumarate, TDF). TAF has also demonstrated improvement in surrogate laboratory markers of renal and bone safety as compared to TDF in clinical trials in combination with other antiretroviral agents. Data show that because TAF enters cells, including HIV-infected cells, more efficiently than TDF, it can be given at a much lower dose and there is 90 percent less tenofovir in the bloodstream.

Monday, November 16, 2009

Pentamidine for muscle-wasting-disease.....


Pentamidine (salt of isethionate) is an antimicrobial medication primarily given for prevention and treatment of Pneumocystis pneumonia (PCP) caused by Pneumocystis jirovecii, also formerly known as Pneumocystis carinii pneumonia (PCP), a severe interstitial type of pneumonia often seen in patients with HIV infection. PCP is considered an 'opportunistic infection', endangering only immunodeficient patients such as those with HIV/AIDS. Pentamidine is also used as a prophylactic in patients receiving chemotherapy, as they also have a depressed immune system as a direct side-effect of the drugs used. The mortality of untreated PCP is very high. Additionally, pentamidine has good clinical activity in treating leishmaniasis, sleeping sickness caused by different strains of Trypanosoma, and yeast infections caused by the organism Candida albicans. Pentamidine is also used as a prophylactic antibiotic for children undergoing treatment for leukemia.

Apart from these diverse applications Pentamidine, has been recently found to become a new therapy for an inherited muscular wasting disease, according to researchers at the University of Oregon and the University of Rochester School of Medicine and Dentistry in New
York.

Pentamidine, when tested in genetically altered mice, counters genetic splicing defects in RNA that lead to type 1 myotonic dystrophy - one of nine types of muscular dystrophy -- also known as DM1 and Steinart's disease. Researchers found that pentamidine disrupted the complexes formed by the expanded repeats and the MBNL protein that becomes stuck to them, allowing the protein to return to its proper location in the cell. The compound also inhibited interactions of MBNL with the cytosine-uracil-guanine repeats and partially rescued two splicing errors in the mice. Though further study like testing with patients suffering from DM1 is still to be established, its a good achievement.

Source : http://uonews.uoregon.edu/archive/news-release/2009/11/possible-help-fight-against-muscle-wasting-disease

Thursday, July 21, 2022

FDA Approves Amvuttra (vutrisiran) for the Treatment of the Polyneuropathy of Hereditary Transthyretin-Mediated Amyloidosis in Adults



Alnylam Pharmaceuticals, Inc. (Nasdaq: ALNY), the leading RNAi therapeutics company, today announced that the U.S. Food and Drug Administration (FDA) approved Amvuttra (vutrisiran), an RNAi therapeutic administered via subcutaneous injection once every three months (quarterly) for the treatment of the polyneuropathy of hereditary transthyretin-mediated (hATTR) amyloidosis in adults. hATTR amyloidosis is a rare, inherited, rapidly progressive, and fatal disease with debilitating polyneuropathy manifestations, for which there are few treatment options. The FDA approval is based on positive 9-month results from the HELIOS-A Phase 3 study, where Amvuttra significantly improved the signs and symptoms of polyneuropathy, with more than 50 percent of patients experiencing halting or reversal of their disease manifestations.
“Twenty years ago, Alnylam was founded with the bold vision for RNA interference to make a meaningful impact on the lives of people around the world in need of new approaches to address serious diseases with significant unmet medical needs, such as hATTR amyloidosis. Today, Amvuttra has the potential to change the standard of care for people living with the polyneuropathy of this devastating disease,” said Yvonne Greenstreet, MBChB, Chief Executive Officer of Alnylam Pharmaceuticals. “We are so thankful to the patients, families and investigators involved in making Amvuttra a reality for the hATTR amyloidosis community. As the fifth RNAi therapeutic developed by Alnylam to receive regulatory approval in less than four years, we believe Amvuttra represents an important milestone that brings us one step closer to achieving our P5x25 goals aimed at Alnylam’s transition to a leading biotech company.”

The FDA approval of Amvuttra is based on positive 9-month results from HELIOS-A, a global, randomized, open-label, multicenter, Phase 3 study that evaluated the efficacy and safety of Amvuttra across a diverse group of patients with hATTR amyloidosis with polyneuropathy. 164 patients with hATTR amyloidosis were randomized 3:1 to receive either 25 mg of vutrisiran (N=122) via subcutaneous injection once every three months or 0.3 mg/kg of patisiran (N=42) via intravenous infusion once every three weeks (reference group) for 18 months. The efficacy of Amvuttra was assessed by comparing the Amvuttra group in HELIOS-A with the placebo group (n=77) from the landmark APOLLO Phase 3 study of patisiran, a randomized controlled study in a comparable patient population.
Amvuttra met the primary endpoint of the study, the change from baseline in the modified Neuropathy Impairment Score + 7 (mNIS+7) at 9 months. Treatment with Amvuttra (N=114) resulted in a 2.2 point mean decrease (improvement) in mNIS+7 from baseline as compared to a 14.8 point mean increase (worsening) reported for the external placebo group (N=67), resulting in a 17.0 point mean difference relative to placebo (p<0.0001); by 9 months, 50 percent of patients treated with Amvuttra experienced improvement in neuropathy impairment relative to baseline.

Amvuttra also met all secondary endpoints in the study at 9 months, with significant improvement in the Norfolk Quality of Life Questionnaire-Diabetic Neuropathy (Norfolk QoL-DN) score and timed 10-meter walk test (10-MWT), and improvements were observed in exploratory endpoints, including change from baseline in modified body mass index (mBMI), all relative to external placebo. Efficacy results at 18 months were consistent with 9-month data, with Amvuttra achieving statistically significant improvements compared to external placebo for all secondary endpoints including mNIS+7, Norfolk QoL-DN, 10-MWT and mBMI, and non-inferiority in serum TTR reduction relative to the within-study patisiran reference group.

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Sunday, January 18, 2009

Structure of key Ebola protein solved.....

The Ebola virus can cause hemorrhagic fever that is usually fatal. According to the Center for Disease Control and Prevention, outbreaks have caused more than 1,000 deaths, mostly in Central Africa, since it was first recognized in 1976. Approved treatments for these infections are currently lacking. The Ebola VP35 protein is multifunctional, acting as a component of the viral RNA polymerase complex, a viral assembly factor, and an inhibitor of host interferon (IFN) production. Mutation of select basic residues within the C-terminal half of VP35 abrogates its dsRNA-binding activity, impairs VP35-mediated IFN antagonism, and attenuates EBOV growth in vitro and in vivo. Because VP35 contributes to viral escape from host innate immunity and is required for EBOV virulence, understanding the structural basis for VP35 dsRNA binding, which correlates with suppression of IFN activity, is of high importance.

A team led by Gaya Amarasinghe, an assistant professor in biochemistry, biophysics and molecular biology, has recently solved the structure from a key part of the Ebola protein known as VP35. This protien interferes with the natural resistance of host cells against viral infections. when viruses infect cells, the host immune system can fight to eventually clear the virus. But with Ebola infections, the ability of the host to mount a defense against the invading virus is lost
I think this if not controlled will be like deadly epidemic AIDS (and even worst than this...), because of the fact that the VP35 protein interferes with the host's innate immune pathways that form the first line of defense against pathogens. With the advent of technologies like combination of X-ray crystallography and nucleic magnetic resonance spectroscopy the team has achieved the structure by using non-infectious protein samples. Hope this template (known structure) will help the drug discoverers to identify and design drugs that potentially bind with VP35 and their by substantiate anti-viral drug discovery. Congrats to Gaya Amarashinghe and his team. More ....




Wednesday, January 26, 2022

FDA Approves Leqvio (inclisiran), First-in-Class siRNA to Reduce Low-Density Lipoprotein Cholesterol (LDL-C)


Novartis  announced the US Food and Drug Administration (FDA) approval of Leqvio® (inclisiran), the first and only small interfering RNA (siRNA) therapy to lower low-density lipoprotein cholesterol (also known as bad cholesterol or LDL-C) with two doses a year, after an initial dose and one at three months.

"Leqvio is a revolutionary approach to lower LDL-C, and creates new possibilities for how healthcare systems can impact cardiovascular disease, a defining public health challenge of our time," said Vas Narasimhan, Novartis CEO. "We now have the opportunity, working together with partners, to provide this first-ever approved LDL-C–lowering siRNA-based therapy to tackle ASCVD at scale across the United States."

Leqvio is indicated in the United States as an adjunct to diet and maximally tolerated statin therapy for the treatment of adults with clinical atherosclerotic cardiovascular disease (ASCVD) or heterozygous familial hypercholesterolemia (HeFH) who require additional lowering of LDL-C. The effect of Leqvio on cardiovascular morbidity and mortality is being explored in clinical trials currently underway.

"ASCVD is a substantial public health burden affecting 30 million Americans," said Norman Lepor, MD, a Los Angeles based cardiologist and a clinical investigator in the Phase III clinical program for Leqvio. "As a first-of-its-kind siRNA therapy, Leqvio works differently than other cholesterol treatments, with twice-yearly dosing that makes it a compelling option for the millions of people with ASCVD already on cholesterol-lowering medications struggling to reach their LDL-C target."

Leqvio reduces the amount of LDL-C in the bloodstream by improving the liver's natural ability to prevent the production of a protein that plays a role in keeping circulating cholesterol levels high6,7. It is a subcutaneous injection given by a healthcare provider with an initial dose, then again at three months, and then every six months1. This approach may help those who have trouble sticking to medicines that are self-administered and have greater dosing frequency. Leqvio will be available in early January 2022.

"People with ASCVD have most likely experienced a heart attack or stroke from high cholesterol, causing a burden on the family and having a negative impact on lives," said Andrea Baer, Executive Director of The Mended Hearts, Inc. "One of the first steps to improving patients' health is to manage high cholesterol and we're encouraged that this new twice-a-year treatment offers a new option." 

The FDA approval was based on results from the comprehensive Phase III ORION-9, -10 and -11 clinical trials, in which all 3,457 participants with ASCVD or HeFH had elevated LDL-C while receiving a maximally tolerated dose of statin therapy2,3. In the Phase III trials at month 17, Leqvio delivered effective and sustained LDL-C reduction of up to 52% vs. placebo and was reported to be well-tolerated with a safety profile shown to be comparable to placebo2,3. The most common side effects were mild to moderate injection site reaction (including pain, redness and rash), joint pain, urinary tract infection, diarrhea, chest cold, pain in legs or arms and shortness of breath2,3.

Novartis has obtained global rights to develop, manufacture and commercialize Leqvio under a license and collaboration agreement with Alnylam Pharmaceuticals, a leader in RNAi therapeutics.




Ref : https://en.wikipedia.org/wiki/Inclisiran
https://www.bachem.com/news/galnac-delivering-promise-of-oligonucleotides/

Thursday, December 25, 2008

A new experimental drug "antagomir" (antisense oligonucleotide) as an anti- miR-21 agent..

MicroRNAs are small scraps of RNA comprising around 20 nucleotides and it is only recently that scientists have discovered their power which is they can regulate the expression (switching on and off) of a large number of human genes (they are like "master controllers"). And also these are the culprits (when microRNAs don't appear in the right place at the right time within cells) for diseases such as cancer, viral infections, inflammatory diseases and metabolic disorders. The potential to use them as targets for drugs is obvious and possibly explains why this is one of the fastest growing areas of development for new drugs and treatments.

Scientists already knew that microRNA was involved in switching genes on and off in the heart, but the underlying mechanisms and how they relate to the development of particular types of heart disease and their potential as drug targets were still relatively unknown.

Thum and colleagues discovered that miR-21 was expressed in the heart's fibroblast cells (cells that make the scaffolding of collagen or connective tissue that hold the shape of the organ) and were in greater numbers in lab mice bred to have heart failure and also in human tissue from patients who had heart failure.

In this study they showed that increasing expression of miR-21 changed the way that signals behaved in a previously unknown stress response pathway that involved the gene sprouty-1 and the MAP-kinase signaling pathway. In turn, increasing the activity of the MAP-kinase pathway led to a number of signs of heart failure, such as enhanced fibroblast survival, increased secretion of factors like fibroblast growth factor, tissue scarring (fibrosis), and cardiac dysfunction including cellular hypertrophy.

The researchers proved they could administer anti-miR-21 effectively to the heart by monitoring it with fluorescence staining. Then, in a mouse transaortic constriction model of human heart failure, they showed that anti-miR-21 silenced increased expression of miR-21 and corrected downstream changes in sprouty-1 and MAP-kinase signaling.

The interesting thing is their conclusion : Anti-miR-21, showed the most statistically significant improvement in the heart failure mouse model when given before induction of heart failure and for as long as three weeks afterward and it might be possible to target entire disease pathways with one drug. Contrats Dr. Thomas Thum.