Pharmaceutical companies have launched new drugs at a fast rate after years of lackluster activity, but selling them has been a challenge, The Wall Street Journal reported. Last year, the Journal said there were 39 new drugs produced. These include blood thinners introduced by Johnson & Johnson, Pfizer Inc and Bristol-Myers Squibb Co, as well as therapies from Pfizer and GlaxoSmithKline for autoimmune disorders. However, the marketplace has become increasingly skeptical and concerned about cost, the report added.

The report said the drug manufacturers were having difficulty persuading doctors, patients and insurance firms that the new drugs are worth the premium prices asked for them. They are especially dubious about the newly-launched drugs for illnesses that have existing and effective therapies.

Citing data from ZS Associates, the report said only 13 of the 271 drugs launched since 2006 have posted yearly sales of over $1 billion. This was a decrease from the 33 of the 257 drugs that had notched the same level of sales in the previous five years. There were 500 drug launches evaluated by ZS Associates, a sales and marketing management consultant.

The report quoted Ganesh Vedarajan, who said, "Blockbusters are not going to be that common anymore." Vedarajan is the head of the oncology and specialty therapeutics practice of ZS.

The report said drugs that were introduced from 2006 to 2010 posted average annual sales of $143 million in the US three years after being launched in the market. In the previous five-year period, the figure was much higher at $208 million. The consequence for drug makers is that they will have more difficulty overcoming the dent in sales, which have been affected by the competition coming from generic drug makers for their previous blockbusters, the report said. From 2011 to 2015, drugs that have posted close to $100 billion in sales in the US are set to lose patent protection, the Journal added.