Introduction

Healthcare markets, including prescription drugs, often operate under price opacity. But this is changing due to emerging search technologies and real-time benefit check systems that are being integrated into the computerized systems (EMR systems) used in clinical care.

These new price transparency technologies will have greatest value when there is a high level of variation among the prices of prescription drugs. Such variation could occur along many dimensions: package size (i.e., quantity, e.g., number of pills), medication form (e.g., capsule or tablet), manufacturer (for generic drugs), etc.

Here is a look at price variation among a large set of prescription drugs, especially on the Form dimension.

Load the Data

For analysis it might be good to consider just the price observations between # 2000 (Jan 1) and 2020 (Dec 31).

Data Sample

NDC Category Generic_Name Qty Dosage Mfr_Name Form LOB AWPPrice WACPrice AWPDate WACDate awp_per_30ds wac_per_30ds Label_Name Brand
16729017501 Antidepressant AMITRIPTYLINE HCL 100 100MG ACCORD HEALTHCARE Tablet Commercial 2.5 0.86 2014-12-03 2020-02-07 88 31 AMITRIPTYLIN TAB 100MG Generic
00378268501 Antidepressant AMITRIPTYLINE HCL 100 100MG MYLAN Tablet Commercial 1.1 0.10 2001-04-07 2002-05-30 80 36 AMITRIPTYLIN TAB 100MG Generic
00378268501 Antidepressant AMITRIPTYLINE HCL 100 100MG MYLAN Tablet Commercial 2.5 1.14 2014-07-16 2014-07-16 80 36 AMITRIPTYLIN TAB 100MG Generic
16714045001 Antidepressant AMITRIPTYLINE HCL 100 100MG NORTHSTAR RX Tablet Commercial 1.4 NA 2015-01-04 NA 79 39 AMITRIPTYLIN TAB 100MG Generic
16714045001 Antidepressant AMITRIPTYLINE HCL 100 100MG NORTHSTAR RX Tablet Commercial 2.3 1.14 2017-03-17 2015-01-12 79 39 AMITRIPTYLIN TAB 100MG Generic
16714045001 Antidepressant AMITRIPTYLINE HCL 100 100MG NORTHSTAR RX Tablet Commercial 2.2 1.09 2015-01-14 2015-01-04 79 39 AMITRIPTYLIN TAB 100MG Generic

Price Groups

To check whether a “drug” has different prices for different forms, we first define what a “Drug Configuration” is – a tuple comprising (Generic_Name, Qty, Dosage, LOB).

Note: “Manufacturer” is not part of the grouping, because products from df.drug.prices manufacturer that are chemically the same drug (same Generic_Name, same Dosage) are still substitutable.

The “Form” is not included in defining the configuration here, because our interest is to see whether simply varying Form can lead to a different price within the same drug configuration.

We see that there are 19 drug configurations (i.e., matching Generic_Name, Qty, Dosage, LOB) that have prices in at least 2 forms. Let’s get prices and other attributes for these drugs.

Visualizing Prices by Form

The price comparisons are displayed for every 2 (or more) Forms. However, note that some of these comparisons are not medically meaningful – eg Tablet vs 24 hour Extended Release Capsule.

Examples: Using all 4 Price Types

Let’s look at one drug BUPROPION HCL ( 30 ) 150MG.

Generic_Name Qty Dosage LOB count NDC Category Mfr_Name Form AWPPrice WACPrice AWPDate WACDate awp_per_30ds wac_per_30ds Label_Name Brand group
BUPROPION HCL 30 150MG Commercial 2 16729044310 Antidepressant ACCORD HEALTHCARE Tablet Extended Release 24 Hour 5.22 0.18 2018-10-30 2018-10-30 184 6.5 BUPROPN HCL TAB 150MG XL Generic BUPROPION HCL 30 150MG Commercial
BUPROPION HCL 30 150MG Commercial 2 00591333130 Antidepressant ACTAVIS PHARMA Tablet Extended Release 24 Hour 5.22 1.30 2008-11-26 2010-10-01 193 48.2 BUPROPN HCL TAB 150MG XL Generic BUPROPION HCL 30 150MG Commercial
BUPROPION HCL 30 150MG Commercial 2 68084070825 Antidepressant AMERICAN HEALTH PACKAGING Tablet Extended Release 12 Hour 0.73 0.61 2015-04-01 2015-04-01 22 18.4 BUPROPION TAB 150MG SR Generic BUPROPION HCL 30 150MG Commercial
BUPROPION HCL 30 150MG Commercial 2 68001032204 Antidepressant BLUE POINT LABORATORIES Tablet Extended Release 24 Hour 4.77 0.68 2017-04-07 2019-02-01 171 24.4 BUPROPN HCL TAB 150MG XL Generic BUPROPION HCL 30 150MG Commercial
BUPROPION HCL 30 150MG Commercial 2 69097087502 Antidepressant CIPLA USA Tablet Extended Release 24 Hour 4.77 0.33 2016-08-22 2020-07-22 183 28.0 BUPROPN HCL TAB 150MG XL Generic BUPROPION HCL 30 150MG Commercial
BUPROPION HCL 30 150MG Commercial 2 43598065530 Antidepressant DR.REDDY’S LABORATORIES, INC. Tablet Extended Release 24 Hour 4.77 0.42 2017-08-22 2017-08-22 166 14.5 BUPROPN HCL TAB 150MG XL Generic BUPROPION HCL 30 150MG Commercial

And another: VENLAFAXINE HCL 90 150MG.

Generic_Name Qty Dosage LOB count NDC Category Mfr_Name Form AWPPrice WACPrice AWPDate WACDate awp_per_30ds wac_per_30ds Label_Name Brand group
VENLAFAXINE HCL 90 150MG Commercial 2 52343013390 Antidepressant ACETRIS HEALTH Capsule Extended Release 24 Hour 0.14 0.11 2016-08-16 2016-08-16 4.1 3.4 VENLAFAXINE CAP 150MG ER Generic VENLAFAXINE HCL 90 150MG Commercial
VENLAFAXINE HCL 90 150MG Commercial 2 65862069790 Antidepressant AUROBINDO PHARMA Capsule Extended Release 24 Hour 5.08 0.67 2012-01-01 2012-01-01 177.0 23.2 VENLAFAXINE CAP 150MG ER Generic VENLAFAXINE HCL 90 150MG Commercial
VENLAFAXINE HCL 90 150MG Commercial 2 00527260446 Antidepressant LANNETT Tablet Extended Release 24 Hour 7.54 3.61 2019-12-12 2019-12-12 235.3 112.7 VENLAFAXINE TAB 150MG ER Generic VENLAFAXINE HCL 90 150MG Commercial
VENLAFAXINE HCL 90 150MG Commercial 2 16714090502 Antidepressant NORTHSTAR RX Tablet Extended Release 24 Hour 7.55 6.29 2019-08-12 2019-08-12 226.4 188.7 VENLAFAXINE TAB 150MG ER Generic VENLAFAXINE HCL 90 150MG Commercial
VENLAFAXINE HCL 90 150MG Commercial 2 00093738698 Antidepressant TEVA PHARMACEUTICALS USA Capsule Extended Release 24 Hour 5.08 0.37 2010-07-01 2015-11-19 174.4 12.6 VENLAFAXINE CAP 150MG ER Generic VENLAFAXINE HCL 90 150MG Commercial
VENLAFAXINE HCL 90 150MG Commercial 2 13668002090 Antidepressant TORRENT PHARMACEUTICALS Capsule Extended Release 24 Hour 5.08 0.50 2011-06-01 2013-02-05 162.6 16.0 VENLAFAXINE CAP 150MG ER Generic VENLAFAXINE HCL 90 150MG Commercial

All Drugs, Price Comparison Using AWPPrice_1

You can see both price variation by Form, and price variation across the 20 years of data.

For instance for Fluoxetine 10 Mg, until 2016 it didn’t matter whether you picked Tablet or Capsule (and so Doctors might get trained to ignore Form for this medication), but after that Capsule prices are much higher than Tablet prices.

All Drugs, Price Comparison Using WACPrice_1

All Drugs, Price Comparison Using awp_per_30ds

All Drugs, Price Comparison Using wac_per_30ds

Comparing Form1 and Form2 prices across different package sizes

Since we’re working with normalized prices (i.e., price per pill and price for 30 days supply) - and since anyway there doesn’t seem to be much use of quantity discounts, we can compare price of a drug in Form1 and size1 against Form2 and size2.

Now one can also see whether there is any unit-price variation by Quantity. We see that there are 19 drugs (i.e., matching Generic_Name, Dosage, LOB) that have prices in at least 2 forms.

Using AWPPrice_1

Across all quantities

This time we’ll add Qty as a variable, i.e., the plot will mix per-pill prices in various package sizes (Qty) - and use size=log(Qty) to separate them out.

10 mg pills

20 mg pills