||Norval PY, Blomberg B, Kitler ME, Dye C & Spinaci
||Estimate of the global market for Rifampicin-containing
fixed-dose combination tablets
|| INT J TB & LUNG DIS 1999, 3 (Suppl), S292-S300
The WHO and the IUATLD have recommended fixed dose
combination (FDC) tablets containing Rifampicin for TB treatment.
However, due to variation in bioavailability of the Rifampicin and
quality of Rifampicin in FDCs have prevented their large scale use
resulting in lower production and higher prices beyond affordability
in developing countries. In this paper, the authors estimate the
potential size of the market for Rifampicin containing FDCs assuming
that all the currently marketed Rifampicin will be sold in FDCs.
The quantity of Rifampicin is estimated by the following equations
: the quality of Rifampicin per treatment regimen multiplied by
the number of TB cases treated in public and private sector. The
future size of the market for FDCs will be influenced by trends
in numbers of cases, the ratio of cases treated in the public v/s
the private sector and the ratio of cases not treated at all. The
future trends of the TB epidemic may be influenced by several factors
such as implementation of control strategy, commitment of government
for TB control and the impact of the HIV epidemic. Hence, the authors
have decided to provide an estimate of the present market.
WHO collected the information on the use of FDCs
in public sector through a questionnaire; 85 countries representing
about 90% of the worlds TB cases responded to the WHO questionnaire.
About 50% of the 85 countries use Rifampicin as FDCs in the public
sector, however most of these are small countries. In the public
sector, an estimated 23.8% of the total number of notified TB cases
are treated with two or three drug FDCs. In the public sector it
is estimated that the global amount of Rifampicin used yearly to
treat 3.57 million TB cases is 123.7 metric tons, representing 78.9%
million tablets of 150 mg Rifampicin or 34 g per TB case. In the
private sector, it is estimated that 2.54 million TB cases are treated
using 99.9 metric tons, representing 666.3 million tablets of 150
mg Rifampicin or 39 g per case. Thus, the potential global market
for the four drug FDC tablet (R-150 mg, H-75 mg, PZA-400 mg and
Emb-75 mg) is 305 million tablets per year, 105 and 200 million
of which would be distributed in the public and private sectors
respectively. The uncertainty of the estimate remains considerable,
as shown by the 90% confidence intervals. In conclusion, the study
demonstrated a large potential global market for FDCs that should
encourage pharmaceutical manufacturers to produce WHO recommended
dosages of FDCs at affordable prices. Current use of Rifampicin
in the FDCs is only 25% of the total Rifampicin used in the world.
|KEY WORDS: DRUG THERAPY; DRUG COMBINATIONS; BIOAVAILABILITY;
PRIVATE SECTOR; PUBLIC HEALTH SECTOR; GENEVA.