Stockholm, Sweden

Year-End Report, 2020

Positive Topline Results from Pivotal Phase 3 NefIgArd Trial

"On November 8, 2020, we announced positive topline readout

of Part A of our Phase 3 pivotal trial, NefIgArd. The results were statistically significant and clinically relevant: proteinuria

showed a 31% reduction versus baseline, a stronger effect than what was seen in the Phase 2b (27%), which is generally not expected

when moving from Phase 2 to Phase 3. In addition, eGFR was stabilised in the treated patient population, which in the end is the

true treatment goal. This potentially disease modifying effect is to our knowledge unique to Nefecon, which we find extremely exciting,

and we look forward to our interactions with regulators during the year as we progress towards potential approval.

also concluded the purchase of a controlling block in Genkyotex in Q4. This is a company we had followed and where we found the

clinical data intriguing and their approach clearly differentiated. Genkyotex had positive interactions with the FDA in 2020, which

resulted in an adaptive pivotal Phase 2/3 design in PBC and they also initiated a Phase 1 PK study to look into higher dosing,

which read out positively in early 2021. We feel excited about taking on a pioneering role in the area of NOX inhibitors and to

initiate studies in PBC, as well as on the basis of comprehensive and compelling animal-based data launch a proof of concept trial

in head and neck cancer where today's immunotherapy has limited reach."

Ren e Aguiar-Lucander, CEO

October 1 - December 31, 2020

Significant events during Q4 2020, in summary

Significant events after the end of reporting period, in

Investor Presentation February 18, 14:30 CET

Audio cast with teleconference, Q4 2020, February 18, 2021,

14:30 (Europe/Stockholm)

Webcast: https://tv.streamfabriken.com/calliditas-therapeutics-q4-2020

Teleconference: SE: +46850558356 UK: +443333009262 US: +18338230586

further information, please contact:

Ren e Aguiar-Lucander, CEO at Calliditas

Mikael Widell, Investor Relations

Email: mikael.widell@calliditas.com

Telephone: +46 703 11 99 60

information in the press release is information that Calliditas is obliged to make public pursuant to the EU Market Abuse Regulation.

The information was submitted for publication, through the agency of the contact persons set out above, at 07:00 CET on February

About Calliditas Therapeutics

Calliditas Therapeutics is a specialty

pharmaceutical company based in Stockholm, Sweden focused on identifying, developing and commercializing novel treatments in orphan

indications, with an initial focus on renal and hepatic diseases with significant unmet medical needs. Calliditas' lead product

candidate, Nefecon, is a proprietary, novel oral formulation of budesonide, an established, highly potent local immunosuppressant,

for the treatment of the autoimmune renal disease IgA nephropathy, or IgAN, for which there is a high unmet medical need and there

are no approved treatments. Calliditas is running a global Phase 3 study within IgAN and, if approved, aims to commercialize Nefecon

in the United States. Calliditas is also planning to conduct clinical trials with NOX inhibitors in PBC and oncology. Calliditas

is listed on Nasdaq Stockholm (ticker: CALTX) and The Nasdaq Global Select Market (ticker: CALT).

Forward-Looking Statements

This press release contains forward-looking

statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation,

statements regarding Calliditas' strategy, business plans and focus. The words "may," "will," "could,"

"would," "should," "expect," "plan," "anticipate," "intend,"

"believe," "estimate," "predict," "project," "potential," "continue,"

"target" and similar expressions are intended to identify forward-looking statements, although not all forward-looking

statements contain these identifying words. Any forward-looking statements in this press release are based on management's

current expectations and beliefs and are subject to a number of risks, uncertainties and important factors that may cause actual

events or results to differ materially from those expressed or implied by any forward-looking statements contained in this press

release, including, without limitation, any related to Calliditas'' business, operations, clinical trials, supply chain,

strategy, goals and anticipated timelines, competition from other biopharmaceutical companies, and other risks identified in the

section entitled "Risk Factors" Calliditas' reports filed with the Securities and Exchange Commission. Calliditas

cautions you not to place undue reliance on any forward-looking statements, which speak only as of the date they are made. Calliditas

disclaims any obligation to publicly update or revise any such statements to reflect any change in expectations or in events, conditions

or circumstances on which any such statements may be based, or that may affect the likelihood that actual results will differ from

those set forth in the forward-looking statements. Any forward-looking statements contained in this press release represent Calliditas''

views only as of the date hereof and should not be relied upon as representing its views as of any subsequent date.