|
Oral
antidiabetics (A10B) and human insulins and analogues (A10C)
are the main treatments used for diabetes. According to
IMS, the global market for these treatments is expected
to triple over the next ten years. For both oral
antidiabetics and insulins, the increase in the proportion
of the population being diagnosed with Type 2 diabetes and
the launch of new products will drive the expansion of these
classes.
Sales
forecast for the global diabetes market
Source:
IMS
Therapy Forecaster
The
oral antidiabetic market looks set to exhibit the greatest
increase in growth, with the US market being the main driver.
On a global scale, oral antidiabetic sales are currently
worth more than double that of human insulins and analogues.
However, this is largely due to US market dominance - most
of the European countries are exhibiting greater growth
and sales in human insulins and analogues than oral antidiabetics.
The rapid
growth of oral antidiabetics seen from 1997 onwards
was led by the first thiazolidinedione insulin sensitiser,
or glitazone, Glaxo Wellcome's Rezulin (troglitazone),
followed by SmithKline Beecham's (now GlaxoSmithKline) Avandia
(rosiglitazone) and Actos (pioglitazone) from Takeda,
co-promoted by Eli Lilly. Rezulin was withdrawn in March
2000 following reports of serious adverse effects on the
liver.
The increase in sales of oral
antidiabetics can also be linked to the increasing occurrence
of Type 2 diabetes, typically a disease first seen in adulthood;
it is now becoming increasingly common in children. Over
three-quarters of patients with newly diagnosed Type 2 diabetes
are obese and this is thought to be a key risk factor in
the disease.
The future
According to IMS Therapy Forecaster,
and on a global scale, the antidiabetes classes (A10B and
A10C) are forecast to triple in size over the ten-year period
from 2001 to 2011. IMS Therapy Forecaster includes in its
forecasts the events that are likely to influence a market.
For diabetes these include:
There will be an increase
in the proportion of the population diagnosed with Type
2 diabetes and also a greater awareness of impaired glucose
tolerance and syndrome X, a collection of risk factors
for the development of Type 2 diabetes and cardiovascular
disease. The physicians interviewed for this study were
all aware that intervention with a drug or lifestyle change
could reduce the incidence of diabetes. It was also thought
that in the future patients would be diagnosed much earlier
and treated more aggressively to stop these conditions
from developing.
There are four inhaleable
insulin products
in development at the moment. Exubera, a Pfizer,
Aventis and Inhale Therapeutic Systems joint project,
is the most advanced in development and could become available
within two years. Inhaleable insulin could reduce the
number of insulin injections a diabetic requires every
day. Moreover, in Type 2 diabetes it could also reduce
the number of oral antidiabetic drugs required, since
patients will be more likely to accept insulin at an earlier
stage in their treatment regimen. The physicians interviewed
for this study were generally enthusiastic about inhaled
insulin, commenting that it would improve patient compliance.
They did, however, express concern about long term lung
damage and injury.
An interesting area of development
in the A10B class are drugs that are geared towards increasing
the levels of glucagon-like peptide 1 (GLP-1), which is
found in the gut. Studies have been carried out to demonstrate
that GLP-1 secretion is significantly impaired in Type
2 diabetics, and increased levels have the potential to
cause delayed gastric emptying and the stimulation of
insulin secretion. A number of drugs are in development
and it is hoped that this approach will prove to be successful.
New indications:
The US FDA has approved
Bristol-Myers Squibb's Glucophage (metformin) for
use in children. This is of particular importance with
the increasing prevalence of Type 2 diabetes in children,
and is likely to pave the way for other companies to conduct
paediatric safety trials so as to extend usage of their
drugs and increase sales.
Patent expiries for a number
of antidiabetics are anticipated during the forecast period,
which will impact the US market in particular. For example,
the launch of generic Glucophage on the US market in early
2002 is likely to have a large negative impact on the
sales of A10B drugs, since its market share is currently
around 40%.
In the UK, Canada and Italy
physicians are being encouraged to prescribe generic versions
of drugs, as cost-cutting measures. There are and will
be a number of antidiabetic drugs reaching patent expiry
in these countries during the forecast period, including
the glitazone Actos.
IMS
Therapy Forecaster
IMS Therapy Forecaster is an
interactive forecasting system, providing ten-year sales
forecasts for 39 therapeutic classes in eight countries.
It combines statistical extrapolation of IMS MIDAS
data with event-based
forecasting, consolidated from interviews with opinion leaders
and medical practitioners in each country.
|
