Some of this would be easier if T were administered once a month instead of once every 4 weeks. Ignoring weekends and holidays, patients who receive infusions on Dec 1, 2, or 3 should have a second infusion on Dec 29, 30 or 31. Regardless of how we slice the day cake, your December estimate of 90,000 infusions contemplates in the neighborhood of 85,000 patients on T.
Mullen said 40,000 patients by the end of the year would result in "pinch points" in the supply chain.
Let's look at it another way, isolating Tysabri. I think we are in a reasonable ballpark estimating $552 of gross margin to E for each infusion. E gave no guidance on T revenue in its last earnings release or CC (too early). But it did say:
"Elan's investment in SG&A expenses for Tysabri for 2005 in respect of all indications, and including pre-launch costs associated with Tysabri for Crohn's disease in both Europe and U.S. and for MS in Europe, are anticipated to be in the $160.0 million to $180.0 million range."
Let's use the midpoint of 170 million. At a gross margin of 552 per infusion, it will take almost 308,000 infusions in 2005 to produce 170 million of gm.
I don't have a clue as to how fast the ramp-up will be. There is no question there was a bunch of MS patients waiting outside the store for the doors to open. I suspect there will be another surge shortly after the details of the AFFIRM trial two year results are presented in April. If the two year combo trial results are good, another surge as those waiting for the full trial results have all the information these trials will produce in the near term.
To date, the choke point has been the BIIB bureaucracy and insurance companies. When this will ease up, I have no idea.