Saturday, November 7, 2009

Automated Micro-injector a new tool for drug development and genetic engineering...

We had automatic synthesizers (to synthesize simultaneously many chemical intermediates, e.g., Symphony Multiplex peptide Synthesizer etc.), now its the turn of micro injector that has the potential to allow rapid development of a new generation of drugs and genetic engineering organisms, and to better control in-vitro fertilization thanx to Ravi Selvaganapathy (Asst. Prof. of Mech.Eng at McMaster Univ).

Researchers have fabricated a palm-sized, automated, micro-injector that can insert proteins, DNA and other biomolecules into individual cells at volumes exponentially higher than current procedures, and at a fraction of the cost. This will allow scientists to vastly increase preclinical trials for drug development and genetic engineering, and provide greater control of the process. As per the claim by the lead researcher Ravi, "this device is to drug discovery what the assembly line was to the automobile or the silicon chip to information technology,” Congrats for this remarkable achievement details...

Friday, November 6, 2009

Bortezomib for bone cancer in children & teens..


We knew that Bortezomib marketed as Velcade by Millennium Pharmaceuticals is the first therapeutic proteasome inhibitor to be tested in humans. It is approved in the U.S. for treating relapsed multiple myeloma and mantle cell lymphoma (2008). In multiple myeloma, complete clinical responses have been obtained in patients with otherwise refractory or rapidly advancing disease.

Recently researchers from University of Rochester have found more interesting fact that "bortezomib is effective against bone cancer in human cancer cell studies and in mice". In the current study, researchers sought to use Bortezomib (Velcade) against osteosarcoma, an aggressive cancer that starts in bone, spreads quickly and responds poorly to current chemotherapies. The drug, a proteasome inhibitor.

The researchers are excited because of the fact that "a drug already proven safe and effective in treating the most common cancers of the blood may be equally effective in suppressing bone cancer". Bortezomib caused osteosarcoma cells to self destruct, and prevented their spread. claims the researchers. While further studies are needed, these findings suggest that this drug may represent a new treatment option for a devastating disease and an effective complement to current chemotherapies. Congrats for this achievement.

More : http://www.urmc.rochester.edu/news/story/index.cfm?id=2676



Thursday, November 5, 2009

Lovastatin-synthesizing enzyme successfully reconstituted...


Lovastatin is a member of the drug class of statins, used for lowering cholesterol (hypolipidemic agent) in those with hypercholesterolemia and so preventing cardiovascular disease. Lovastatin is a naturally occurring drug found in food such as oyster mushrooms and red yeast rice. When I was working with a Banglore based company (Biocon), they did try this compound and I think the company is marketing this drug now. As for as my knowledge goes there were two ways to synthesise 'biosynthesis using Dield-Alder catalyzed cyclization' & 'biosyntheis using broadly specific acyltransferase'

Dield-Alder catalysed cyclisation : In vitro formation of a triketide lactone using a genetically-modified protein derived from 6-deoxyerythronolide B synthase has been demonstrated. The stereochemistry of the molecule supports the intriguing idea that an enzyme-catalyzed Diels-Alder reaction may occur during assembly of the polyketide chain. It thus appears that biological Diels-Alder reactions may be triggered by generation of reactive triene systems on an enzyme surface.

Biosynthesis using broadly specific acyltransferase : It has been found that a dedicated acyltransferase, LovD, is encoded in the lovastatin biosynthetic pathway. LovD has a broad substrate specificity towards the acyl carrier, the acyl substrate and the decalin acyl acceptor. It efficiently catalyzes the acyl transfer from coenzyme A thoesters or N-acetylcysteamine (SNAC) thioesters to monacolin J. The biosynthesis of lovastatin is coordinated by two iterative type I polyketide syntheses and numerous accessory enzymes. Nonketide, the intermediate biosynthetic precursor of lovastatin, is assembled by the upstream megasynthase LovB (also known as lovastatin nonaketide synthase), enoylreductase LovC, and CYP450 oxygenases.

Recently more interesting out come from a group of UCLA researchers is that, for the first time thy have successfully reconstituted in the laboratory the enzyme responsible for producing the blockbuster cholesterol-lowering drug lovastatin. As per the claim by the researchers, the lovastatin-synthesizing enzyme is one of the most interesting but least understood of the polyketide synthases, which are found in filamentous fungi and which play a crucial role in the synthesis of "small molecule natural products" — pharmacologically or biologically potent compounds produced by living organisms, many of which are the active ingredients in pharmaceuticals.

This finding is of great significance because commonly used antibiotics, such as tetracycline, are produced by polyketide synthases. Polyketides represent a class of 7,000 known structures, of which more than 20 are commercial drugs, including the immunosuppressant rapamycin, the antibiotic erythromycin and the anticancer drug doxorubicin. In their study studied the enzyme that makes a small-molecule precursor to lovastatin. The real difference about this enzyme, is its extraoridnarily large size in comparison to all other enzymes so for studied. As per the claim by the lead researcher Dr. Yi Tang, "It's one of the largest enzymes ever to be reconstituted in a test tube. It is 10 times the size of most enzymes people study & the enzyme has seven active sites and catalyzes more than 40 different reactions that eventually result in an important precursor to lovastatin. Hope with this remarkable achievement, one can prepare many natural products in the lab in the days to come.

Ref : http://www.newsroom.ucla.edu/portal/ucla/ucla-engineering-researchers-have-111812.aspx

Report on the future of RNAi-based therapeutics & diagnostics

The market for RNAi-based therapeutics is forecast to grow from 2013 onwards, as the first products enter the marketplace, to generate sales in excess of US$2.9 billion by 2020. The first siRNA based therapeutics will capitalize on the demand to treat viral infections and ocular conditions and in the longer term companies will be able to target niche areas of high unmet clinical need such as cancer, cardiovascular disease, metabolic disorders, inflammatory and neurological conditions.


More.....Report on the future of RNAi-based therapeutics & diagnostics

Wednesday, November 4, 2009

Positive results from phase 3 clinical trials of Linoclotide ....


Ironwood Pharmaceuticals, Inc. and Forest Laboratories, Inc. recently announced positive top‐line results from two Phase 3 clinical trials assessing the safety and efficacy of once‐daily dosing of the investigational drug linaclotide in patients with chronic constipation (CC). Analyses of the data indicate that in both multicenter, randomized, double‐blind, placebo‐controlled trials, statistical significance was achieved for the primary endpoint of 12‐week complete spontaneous bowel movement (CSBM) overall responder at the two doses studied in each trial (133 mcg/day: p‐values≤0.0012 and 266 mcg/day: p‐values<0.0001). In both trials, statistical significance (p<0.01) was achieved for all prespecified secondary endpoints, which included measures of bloating, abdominal discomfort, and average weekly CSBMs.

About Linaclotide :

Linaclotide (see the structure) is an orally delivered peptide that acts locally in the gut with no detectable systemic exposure at therapeutic doses and is intended for once‐daily administration. Linaclotide can be synthesized by solid-phase technology using Fmoc protections. Amino acids are coupled using DCC/HOBT and Fmoc groups are removed by means piperidne .Cysteinethiol groups are protected with trityl and cleavage of the peptide from the resin is done by TFA.

Mode of action :

Linoclotide acts agonist of guanylate cyclase type‐C (GC‐C), a receptor found on the lining of the intestine. Activation of GC‐C leads to increases in intracellular and extracellular cGMP. In preclinical models, extracellular cGMP inhibited afferent nerve firing and positively affected markers of abdominal pain, while intracellular cGMP led to activation of anion channels which stimulated anion and fluid secretion into the intestine, leading to accelerated intestinal transit. Linaclotide is a first‐in‐class compound in Phase 3 clinical development for the treatment of IBS‐C and CC.

Ref : http://www.ironwoodpharma.com/newsPDF/Linaclotide.Ph3.CC.results.11.02.09.pdf

Tuesday, November 3, 2009

Monday, November 2, 2009

FDA authorizes emergency use of IV antiviral "Peramivir"...

As for as my knowledge goes Peramvir, is an experimental antiviral drug, and being developed by BioCryst Pharmaceuticals for the treatment of influenza. Peramivir is a neuraminidase inhibitor, acting as a transition-state analogue inhibitor of influenza neuraminidase and thereby preventing new viruses from emerging from infected cells.

The development of peramivir is supported by the US Department of Health and Human Services as part of the US government's effort to prepare against the threat of an influenza pandemic.

The drug has had a long history. An oral formulation was abandoned by Johnson and Johnson due to poor bioavailability. BioCryst Pharmaceuticals is now developing a injectable version, in partnership with Green Cross Pharmaceuticals in South Korea and with Shionogi Pharmaceuticals in Japan. The drug is in Phase II studies

More interesting recent news (Oct. 23, 2009) about this drug is that, FDA has announced the issuing of an emergency use authorization (EUA) for the investigational antiviral drug peramivir intravenous (IV) in certain adult and pediatric patients with confirmed or suspected 2009 H1N1 influenza infection who are admitted to a hospital.

Specifically, IV peramivir is authorized only for hospitalized adult and pediatric patients for whom therapy with an IV drug is clinically appropriate based on one or more of the following reasons:
  1. the patient is not responding to either oral or inhaled antiviral therapy, or
  2. when drug delivery by a route other than an intravenous route -- e.g., enteral (absorbed by the intestines) or inhaled -- is not expected to be dependable or feasible;
  3. for adults only, when the clinician judges IV therapy is appropriate due to other circumstances.....
more..

Sunday, November 1, 2009

Steroid-induced osteoporosis can now be treated with Teriparatide

Steroid-induced osteoporosis can now be treated with Teriparatide

Geron plans to advance clinical program for spinal cord injury

In my earlier blog (Euphoria over Stem Cell Therapy.....) did mentioned that, there are many companies which falsely claimed that they have got technology (stem cell treatment) to treat spinal cord injury. But an established company like Geron, has plan to advance clinical development of its human embryonic stem cell (hESC)-based product, GRNOPC1, for the treatment of spinal cord injury. The plan is expected to enable Geron to re-initiate the Phase I clinical trial of GRNOPC1 in patients with complete thoracic spinal cord injury and to support future expansion of the trial to patients with cervical injuries.


I read earlier about the preclinical studies of GRNOPC1 and the company claimed that it is developing GRNOPC1 for spinal cord injury, but is also exploring application for other neurological diseases, including multiple sclerosis, stroke and Alzheimer disease really interesting to see the results.

As I had an opportunity to talk and work (contract research) with Geron [known for its first-in-class biopharmaceuticals (especially "antisense drugs" from oligonucleotides) for the treatment of cancer and chronic degenerative diseases] company, I know its credentials and am really excited to see some interesting out come from their advance clinical program. All the best....

Ref : http://www.geron.com/media/pressview.aspx?id=1195

Botox for Chronic Regional Pain Syndrome (CRPS). ...


We know that Botulinum toxin is a medication and a neurotoxic protein produced by the bacterium Clostridium botulinum, and is held to be the most toxic substance known to mankind with an LD50 of roughly 0.005-0.05 µg/kg. Despite its greatest known toxic effect, it is also used in very small doses to treat muscle spasms. The acceptance of BTX-A use for the treatment of spasticity and muscle pain disorders is growing, with approvals pending in many European countries and studies on headaches (including migraine), prostatic symptoms, asthma, obesity and many other possible indications are ongoing.

But some interesting findings of the same drug has been presented at the American Society of Plastic Surgeons (ASPS) Plastic Surgery 2009 conference, Oct. 23-27, in Seattle, i.e., botox can be used as a pain medication to fight Chronic Regional Pain Syndrome (CRPS).

The study found injecting Botox into the area affected by pain provides significant pain control. Eight patients suffering from severe pain received an average of nine injections , one every four weeks. All of patients reported a significant improvement (31.25 percent) in their daily pain control that was maintained for up to 17 months. Though the drug has been used to treat many problems like cervical dystonia (CD), strabismus, blepharospasm, primary axillary hyperhidrosis, glabellar lines (wrinkle fighter). this finding is more significant....

Ref : http://www.plasticsurgery.org/Documents/Media/ps2009/19-Botox-Chronic-Pain.pdf