Biotech Strategy Blog

Commentary on Science, Innovation & New Products with a focus on Oncology & Hematology

Posts from the ‘Respiratory’ category

One of the exciting things about the biotechnology industry is its ability to innovate and translate developments in basic science into potential new drugs.

I previously wrote about denufosol in cystic fibrosis (CF), a disease that affects about 30,000 people in the United States and 70,000 worldwide.  The disease is characterized by the accumulation of mucus that leads to bacterial overgrowth and chronic lung infections. Mucus cannot be removed from the lung in CF due to abnormal mucociliary transport resulting from impaired epithelial chloride secretion and sodium hyperabsorption.  This is now known to be due to defective cystic fibrosis transmembrane regulator (CFTR) protein. A good overview of this can be found in the 2006 New England Journal of Medicine Editorial by Felix Ratjen, “Restoring Airway Surface Liquid in Cystic Fibrosis.”

A good overview of the pipeline of new drugs in development for CF can be found on the Cystic Fibrosis Foundation web site.  Vertex in particular has two drugs  (VX-809, VX-770) in late stage development that are cystic fibrosis transmembrane conductance regulators, aimed at increasing CFTR function.  Phase 3 registration data for VX-770 is expected in the first half of 2011. I look forward to writing about the results.

Recently, a team from Johns Hopkins led by Neeraj Vij published a paper in the January 2011 issue of Journal of Immunology on the “Critical Modifier Role of Membrane-Cystic Fibrosis Transmembrane Conductance Regulator-Dependent Ceramide Signaling in Lung Injury & Emphysema.”

The researchers found that lung damage in mice was associated with changes in the amount of CFTR in the cell surface membrane.  Decreases in the amount of CFTR were associated with increased ceramide, a trigger of inflammation of cell-death. Or as the the paper describes it:

“CFTR expression inversely correlates with severity of emphysema and ceramide accumulation in chronic obstructive pulmonary disease subjects compared with control subjects.”

The emergence of inflammation as a key role in chronic disease was the subject of a previous blog post about diabetes, so is interesting to see another area where it is involved.

This basic research shows that developing drugs that target CFTR and mediate ceramide may have an important role to play in the treatment of emphysema, a chronic obstructive pulmonary disease (COPD) that affects 2 million Americans.  Translational medicine that can take basic science and apply it to clinical practice is key to the long term success of the biotechnology industry.

1 Comment

Thanks to Adam Feuerstein of TheStreet for breaking the news this morning, that shares in Inspire Pharmaceuticals (NASDAQ: ISPH) have plunged following the announcement of negative data from the phase 3, TIGER-2 clinical trial for denufosol in cystic fibrosis.

According to the Chief Medical Officer at Inspire Pharma: “The analysis of the primary endpoint, key secondary endpoints and select subgroup populations in TIGER-2 indicates an absence of meaningful treatment benefit in this patient population.

I wrote a blog post last week about denufosol and the hope that this drug offered to cystic fibrosis patients despite the uncertainty about its clinical effectiveness.

The latest data is disappointing and a major setback to Inspire Pharma. It highlights the risk/reward situation that many emerging biotechnology companies face with new product development, the hope that they will make it to market, coupled with the reality that many will fail.

Inspire Pharmaceuticals (NASDAQ:ISPH), a North Carolina based biopharmaceutical company that focuses on products for ophthalmic and pulmonary diseases, recently announced positive results from their phase 3 trial (TIGER-1) of denufosol tetrasodium in patients with Cystic Fibrosis (CF).

Cystic Fibrosis is a genetic disorder that can lead to death as a result of pulmonary complications from airway obstruction, bronchial thickening and accumulation of mucous.  Lung function tests are widely used in the diagnosis, treatment and management of patients with CF.  Measurement of FEV1 (Forced Expiratory Volume in 1 second) is regarded as the best predicator of mortality.  As the disease progresses and the lungs become more obstructed, FEV1 decreases.

Inspire Pharma’s denufosol is an ion-channel regulator that helps keep the airways moist and helps mucous removal in CF patients.  It increases chloride secretion via calcium-activated chloride  channels (CaCCs), inhibits sodium absorption via epithelial sodium channels (ENaCs) and stimulates ciliary beat frequency.  Conveniently for patients, it is being developed as an inhaled drug delivered direct to the lungs by nebulizer.

The phase 3 clinical trial data presented by Dr Frank Accurso at the Annual North American Cystic Fibrosis Conference, and in the paper published in the American Journal of Respiratory and Critical Care Medicine (AJRCCM), showed an improvement in lung function after 24 weeks in patients with mild CF who received daily denusofol by means of a nebulizer.  The primary efficacy endpoint was a change in FEV1:

Source: October 21, 2010 presentation by Frank J. Accurso M.D. to North American Cystic Fibrosis Conference.  Available at Inspire Pharma.

Dr Accurso and his colleagues reported that the results demonstrated:

“Mean change from baseline to Week 24 endpoint in expiratory volume at 1 second (primary efficacy endpoint) was 0.048 L for denufosol (n=178) and 0.003 L for placebo (n=174; P=0.047).”

Despite the significant improvement in FEV1, there was no significant difference between the denufosol and placebo arms in the time to progression to first pulmonary exacerbation, suggesting that its long-term clinical effectiveness remains uncertain.

Source: October 21, 2010 presentation by Frank J. Accurso M.D. to North American Cystic Fibrosis Conference.  Available at Inspire Pharma.

Notwithstanding, these results do offer hope to patients with mild symptoms of Cystic Fibrosis.  Early treatment to maintain lung function may delay the onset of more severe physiological changes and the need for more radical treatment options such as a heart/lung transplant.

Thanks to BBC Health for writing about this topic and giving me the idea for this post.

1 Comment
error: Content is protected !!