Eysuvis/Inveltys scripts

#
# An R script to visualize the sales trajectory of Kala Pharmaceuticals' Eysuvis/Inveltys
#
# (c) 2022 Germain Garand <germain.garand@laposte.net>
#
# This is for information purposes only. Any calculation performed herein could be
# wrong and/or misrepresent reality. Use at your own risk.
#
# License: Creative Commons BY-NC 2.0
#
#  v0.1 - 2022/03/25
#

library(ggplot2)
library(scales)

Sys.setlocale("LC_TIME", "C")

# current week
cw <- as.Date("2022/03/18")

nw <- cw + 7
a <- seq(as.Date("2021/10/01"), cw, "week")
aa <- seq(nw, as.Date("2022/12/30"), "week")
cur <- a
a <- c(a, aa)

b <- seq(as.Date("2021/10/01"), a[length(a)], "months")

eys <- c(
  1664, 1655, 1502, 1669, 1669,
  1599, 1983, 1824, 1305,
  1784, 1938, 1826, 1600, 1460,
  1417, 1761, 1789, 1998,
  1935, 2236, 2313, 1944,
  2314, 2166, 2195,
  rep(0, 2),
  rep(0, 9),
  rep(0, 9),
  rep(0, 9),
  rep(0, 9),
  rep(0, 3)
)
inv <- c(
  2922, 3067, 2876, 2885, 3136,
  3004, 2990, 2938, 2248,
  3006, 2851, 2660, 2107, 2071,
  2348, 2634, 2494, 2764,
  2511, 2816, 2907, 2562,
  2790, 2809, 2598,
  rep(2800, 2),
  rep(2900, 9),
  rep(2900, 9),
  rep(3000, 9),
  rep(3000, 9),
  rep(3000, 3)
)

e <- data.frame(a, eys, inv)
names(e) <- c("Week", "Eysuvis", "Inveltys")

e$Month <- as.Date(cut(e$Week, breaks = "month"))

t = length(cur)-1
cwgr = ( ((eys[t]+eys[t+1])/2) / ((eys[1]+eys[2])/2) )^(1/t)-1
fw = length(a)-length(cur)
for (i in 1:fw)
{
  e$Eysuvis[t+1+i] = e$Eysuvis[t+i] + (e$Eysuvis[t+i]*cwgr)
}

options(scipen=10000)

png("eysuvis_inveltys_projected.png", width=960)
plot(Eysuvis ~ Week, e, type = 'l', col='blue', main="Eysuvis/Inveltys", ylab="Scripts", sub=paste("Eysuvis CWGR: ", format(round(cwgr*100, 2), nsmall=2),"%"), col.sub="blue")
par(new=TRUE)
plot(Inveltys ~ Week, e, type='s', axes=FALSE, ann=FALSE,col='red')
axis(4, e$Inveltys, col='red', col.axis='red')
legend("topleft", inset=.05, c("Eysuvis","Inveltys"), fill=c("blue","red"))
abline(v=c(nw), col="green", lty="dotted")
text(x=nw,y=2600, labels="Data after this line is projected", cex=1, srt=90, col="black")

dev.off()